{"status":"success","metadata":{"ticker":"AOS","year":2026,"quarter":1,"full_year_mode":false,"total_facts":204,"prior_comparison_available":true,"source":{"filing_type":"10-Q","period_end":"March 31, 2026","url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084","value_scale":"millions"},"match_rate":{"quarterly":0.5882352941176471,"ytd":0.0,"instants":1.0,"fallback":0.0},"final_match_rate":1.0,"match_diagnostics":{"quarterly":{"same_filing_q":{"current_count":204,"matched_count":120,"match_rate":0.5882352941176471,"prior_count":151,"match_keys":["tag","date_type","axis_key"],"raw_current_row_count":234,"output_row_count":145,"current_duplicate_group_count":24,"prior_duplicate_group_count":20,"shared_key_count":120},"prior_year_ytd":{"current_count":0,"matched_count":0,"match_rate":0.0,"prior_count":0,"match_keys":["tag","date_type"],"raw_current_row_count":0,"output_row_count":0},"prior_year_instant":{"current_count":77,"matched_count":77,"match_rate":1.0,"prior_count":77,"match_keys":["tag","end","date_type","presentation_role","axis_key"],"raw_current_row_count":77,"current_duplicate_group_count":4,"prior_duplicate_group_count":4,"current_only_count":19,"output_row_count":77},"fallback":{"current_count":18,"matched_count":0,"match_rate":0.0,"prior_count":14,"match_keys":["tag","end","date_type","axis_key"],"raw_current_row_count":18,"missing_tag_count":37,"output_row_count":0},"final":{"current_count":204,"matched_count":204,"match_rate":1.0,"raw_current_row_count":234,"output_row_count":241,"current_only_added_count":19,"fallback_added_count":0,"overlap_prior_value_count":0}}}},"facts":[{"tag":"us-gaap:BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual","date_type":"Q","period_type":"duration","presentation_role":"acquisitionsnarrativedetails","presentation_hierarchy":[{"role":"acquisitionsnarrativedetails","parent":"us-gaap:ImpairedLongLivedAssetsHeldAndUsedLineItems","order":10.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,5.0,4,10.0,9],"section_concept":null,"section_label":null}],"concept_label":"Business Combination, Acquiree's Earnings (Loss) since Acquisition Date, Actual","current_period_value":5.5,"prior_period_value":null,"visual_current_value":5.5,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:BusinessAcquisitionAxis=aos:LeonardValueMember","dimensions":[{"axis":"us-gaap:BusinessAcquisitionAxis","axis_label":"Business Acquisition","member":"aos:LeonardValueMember","member_label":"Leonard Value"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-73","char_anchor":"f-289","text_snippet":"5.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":5.5,"prior_value":null},{"tag":"us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired","date_type":"Q","period_type":"duration","presentation_role":"acquisitionsnarrativedetails|condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","order":2.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,2.0,1,2.0,1],"section_concept":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","weight":-1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","calculation_weight":-1.0,"calculation_order":3.0,"section_label":"Investing Activities"},{"role":"acquisitionsnarrativedetails","parent":"us-gaap:ImpairedLongLivedAssetsHeldAndUsedLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,5.0,4,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Payments to Acquire Businesses, Net of Cash Acquired","current_period_value":470,"prior_period_value":null,"visual_current_value":-470,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-155","text_snippet":"470.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":-470,"prior_value":null},{"tag":"us-gaap:BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual","date_type":"Q","period_type":"duration","presentation_role":"acquisitionsnarrativedetails|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","presentation_hierarchy":[{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,2.0,1],"section_concept":null,"section_label":null},{"role":"acquisitionsnarrativedetails","parent":"us-gaap:ImpairedLongLivedAssetsHeldAndUsedLineItems","order":9.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,5.0,4,9.0,8],"section_concept":null,"section_label":null}],"concept_label":"Business Combination, Acquiree's Revenue since Acquisition Date, Actual","current_period_value":15.9,"prior_period_value":null,"visual_current_value":15.9,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:BusinessAcquisitionAxis=aos:LeonardValueMember","dimensions":[{"axis":"us-gaap:BusinessAcquisitionAxis","axis_label":"Business Acquisition","member":"aos:LeonardValueMember","member_label":"Leonard Value"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-73","char_anchor":"f-288","text_snippet":"15.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":15.9,"prior_value":null},{"tag":"us-gaap:Goodwill","date_type":"Q","period_type":"instant","presentation_role":"acquisitionsscheduleoftheallocationofthefairvalueoftheassetsacquiredandliabilitiesassumedatthedateofacquisitiondetails|condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Assets","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Assets","calculation_weight":1.0,"calculation_order":3.0,"section_label":null},{"role":"acquisitionsscheduleoftheallocationofthefairvalueoftheassetsacquiredandliabilitiesassumedatthedateofacquisitiondetails","parent":"us-gaap:BusinessAcquisitionLineItems","order":4.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"acquisitionsscheduleoftheallocationofthefairvalueoftheassetsacquiredandliabilitiesassumedatthedateofacquisitiondetails","parent":"aos:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsIncludingGoodwill","weight":1.0,"order":4.0}],"calculation_role":"acquisitionsscheduleoftheallocationofthefairvalueoftheassetsacquiredandliabilitiesassumedatthedateofacquisitiondetails","calculation_parent":"aos:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsIncludingGoodwill","calculation_weight":1.0,"calculation_order":4.0,"section_label":null}],"concept_label":"Goodwill","current_period_value":919.9,"prior_period_value":null,"visual_current_value":919.9,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-87","text_snippet":"919.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":919.9,"prior_value":null},{"tag":"us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent","date_type":"Q","period_type":"duration","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","presentation_hierarchy":[{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"OCI, before Reclassifications, Net of Tax, Attributable to Parent","current_period_value":1.7,"prior_period_value":0.7,"visual_current_value":1.7,"visual_prior_value":0.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","member_label":"Accumulated Gain Loss Net Cash Flow Hedge Parent"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-155","char_anchor":"f-581","text_snippet":"1.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-156","char_anchor":"f-582","text_snippet":"0.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":1.7,"prior_value":0.7},{"tag":"us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent","date_type":"Q","period_type":"duration","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","presentation_hierarchy":[{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"OCI, before Reclassifications, Net of Tax, Attributable to Parent","current_period_value":-3.5,"prior_period_value":0.7,"visual_current_value":-3.5,"visual_prior_value":0.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedTranslationAdjustmentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedTranslationAdjustmentMember","member_label":"Accumulated Translation Adjustment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-149","char_anchor":"f-575","text_snippet":"3.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-150","char_anchor":"f-576","text_snippet":"0.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-3.5,"prior_value":0.7},{"tag":"us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent","date_type":"Q","period_type":"duration","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","presentation_hierarchy":[{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":3.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent","current_period_value":-0.1,"prior_period_value":-0.1,"visual_current_value":0.1,"visual_prior_value":0.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember","member_label":"Accumulated Defined Benefit Plans Adjustment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-161","char_anchor":"f-591","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-162","char_anchor":"f-592","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.1,"prior_value":0.1},{"tag":"us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent","date_type":"Q","period_type":"duration","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","presentation_hierarchy":[{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":3.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent","current_period_value":0.4,"prior_period_value":-0.1,"visual_current_value":-0.4,"visual_prior_value":0.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","member_label":"Accumulated Gain Loss Net Cash Flow Hedge Parent"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-155","char_anchor":"f-585","text_snippet":"0.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-156","char_anchor":"f-586","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-0.4,"prior_value":0.1},{"tag":"us-gaap:ReclassificationFromAociCurrentPeriodTax","date_type":"Q","period_type":"duration","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","presentation_hierarchy":[{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AccumulatedOtherComprehensiveIncomeLossLineItems","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Reclassification from AOCI, Current Period, Tax","current_period_value":0.1,"prior_period_value":-0.1,"visual_current_value":0.1,"visual_prior_value":-0.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","member_label":"Accumulated Gain Loss Net Cash Flow Hedge Parent"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-155","char_anchor":"f-583","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-156","char_anchor":"f-584","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.1,"prior_value":-0.1},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":1877.9,"prior_period_value":1855.1,"visual_current_value":1877.9,"visual_prior_value":1855.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-135","text_snippet":"1,877.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-12","char_anchor":"f-234","text_snippet":"1,855.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":1877.9,"prior_value":1855.1},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":164.7,"prior_period_value":164.7,"visual_current_value":164.7,"visual_prior_value":164.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementClassOfStockAxis=aos:CommonStockClassUndefinedMember|us-gaap:StatementEquityComponentsAxis=us-gaap:CommonStockMember","dimensions":[{"axis":"us-gaap:StatementClassOfStockAxis","axis_label":"Statement Class Of Stock","member":"aos:CommonStockClassUndefinedMember","member_label":"Common Stock"},{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:CommonStockMember","member_label":"Common Stock"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-23","char_anchor":"f-193","text_snippet":"164.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-24","char_anchor":"f-194","text_snippet":"164.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":164.7,"prior_value":164.7},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":130,"prior_period_value":130.0,"visual_current_value":130,"visual_prior_value":130.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementClassOfStockAxis=us-gaap:CommonClassAMember|us-gaap:StatementEquityComponentsAxis=us-gaap:CommonStockMember","dimensions":[{"axis":"us-gaap:StatementClassOfStockAxis","axis_label":"Statement Class Of Stock","member":"us-gaap:CommonClassAMember","member_label":"Common Class A"},{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:CommonStockMember","member_label":"Common Stock"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-17","char_anchor":"f-187","text_snippet":"130.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-18","char_anchor":"f-188","text_snippet":"130.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":130,"prior_value":130.0},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":-7.1,"prior_period_value":-6.0,"visual_current_value":-7.1,"visual_prior_value":-6.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember","member_label":"Accumulated Defined Benefit Plans Adjustment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-163","char_anchor":"f-593","text_snippet":"7.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-164","char_anchor":"f-594","text_snippet":"6.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-7.1,"prior_value":-6.0},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":1.1,"prior_period_value":-0.7,"visual_current_value":1.1,"visual_prior_value":-0.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedGainLossNetCashFlowHedgeParentMember","member_label":"Accumulated Gain Loss Net Cash Flow Hedge Parent"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-157","char_anchor":"f-587","text_snippet":"1.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-158","char_anchor":"f-588","text_snippet":"0.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":1.1,"prior_value":-0.7},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":-100.7,"prior_period_value":-110.3,"visual_current_value":-100.7,"visual_prior_value":-110.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedOtherComprehensiveIncomeMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedOtherComprehensiveIncomeMember","member_label":"Accumulated Other Comprehensive Income"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-37","char_anchor":"f-219","text_snippet":"100.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-38","char_anchor":"f-220","text_snippet":"110.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-100.7,"prior_value":-110.3},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":-94.7,"prior_period_value":-103.6,"visual_current_value":-94.7,"visual_prior_value":-103.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AccumulatedTranslationAdjustmentMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AccumulatedTranslationAdjustmentMember","member_label":"Accumulated Translation Adjustment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-151","char_anchor":"f-577","text_snippet":"94.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-152","char_anchor":"f-578","text_snippet":"103.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-94.7,"prior_value":-103.6},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":619,"prior_period_value":605.8,"visual_current_value":619,"visual_prior_value":605.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AdditionalPaidInCapitalMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AdditionalPaidInCapitalMember","member_label":"Additional Paid In Capital"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-29","char_anchor":"f-209","text_snippet":"619.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-30","char_anchor":"f-210","text_snippet":"605.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":619,"prior_value":605.8},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":4019.8,"prior_period_value":3688.8,"visual_current_value":4019.8,"visual_prior_value":3688.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:RetainedEarningsMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:RetainedEarningsMember","member_label":"Retained Earnings"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-35","char_anchor":"f-217","text_snippet":"4,019.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-36","char_anchor":"f-218","text_snippet":"3,688.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":4019.8,"prior_value":3688.8},{"tag":"us-gaap:StockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"changesinaccumulatedothercomprehensivelossbycomponentdetails|condensedconsolidatedbalancesheets|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,6.0,5],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"},{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"changesinaccumulatedothercomprehensivelossbycomponentdetails","parent":"us-gaap:AOCIAttributableToParentNetOfTaxRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Equity, Attributable to Parent","current_period_value":-2954.9,"prior_period_value":-2623.9,"visual_current_value":-2954.9,"visual_prior_value":-2623.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:TreasuryStockCommonMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:TreasuryStockCommonMember","member_label":"Treasury Stock Common"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-43","char_anchor":"f-231","text_snippet":"2,954.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-44","char_anchor":"f-232","text_snippet":"2,623.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-2954.9,"prior_value":-2623.9},{"tag":"us-gaap:AccountsPayableTradeCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrentAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0,1.0,0],"section_concept":"us-gaap:LiabilitiesCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrent","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesCurrent","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Current Liabilities"}],"concept_label":"Accounts Payable, Trade, Current","current_period_value":543,"prior_period_value":541.0,"visual_current_value":543,"visual_prior_value":541.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-97","text_snippet":"543.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-97","text_snippet":"541.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":543,"prior_value":541.0},{"tag":"us-gaap:AccruedLiabilitiesCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrentAbstract","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0,3.0,2],"section_concept":"us-gaap:LiabilitiesCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrent","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesCurrent","calculation_weight":1.0,"calculation_order":3.0,"section_label":"Current Liabilities"}],"concept_label":"Accrued Liabilities, Current","current_period_value":159.4,"prior_period_value":198.6,"visual_current_value":159.4,"visual_prior_value":198.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-101","text_snippet":"159.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-101","text_snippet":"198.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":159.4,"prior_value":198.6},{"tag":"us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":3.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:PropertyPlantAndEquipmentNet","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:PropertyPlantAndEquipmentNet","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment","current_period_value":947.6,"prior_period_value":883.4,"visual_current_value":-947.6,"visual_prior_value":-883.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-83","text_snippet":"947.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-83","text_snippet":"883.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-947.6,"prior_value":-883.4},{"tag":"us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,4.0,3],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquity","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:StockholdersEquity","calculation_weight":1.0,"calculation_order":4.0,"section_label":"Stockholders' Equity"}],"concept_label":"Accumulated Other Comprehensive Income (Loss), Net of Tax","current_period_value":-100.7,"prior_period_value":-110.3,"visual_current_value":-100.7,"visual_prior_value":-110.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-131","text_snippet":"100.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-131","text_snippet":"110.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-100.7,"prior_value":-110.3},{"tag":"us-gaap:AdditionalPaidInCapitalCommonStock","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,2.0,1],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquity","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:StockholdersEquity","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Stockholders' Equity"}],"concept_label":"Additional Paid in Capital, Common Stock","current_period_value":619,"prior_period_value":605.8,"visual_current_value":619,"visual_prior_value":605.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-127","text_snippet":"619.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-127","text_snippet":"605.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":619,"prior_value":605.8},{"tag":"us-gaap:AssetsCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrentAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0,6.0,5],"section_concept":"us-gaap:AssetsCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Assets","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Assets","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Current Assets"}],"concept_label":"Assets, Current","current_period_value":1368.4,"prior_period_value":1422.1,"visual_current_value":1368.4,"visual_prior_value":1422.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-79","text_snippet":"1,368.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-79","text_snippet":"1,422.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":1368.4,"prior_value":1422.1},{"tag":"us-gaap:CashAndCashEquivalentsAtCarryingValue","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrentAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0,1.0,0],"section_concept":"us-gaap:AssetsCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrent","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:AssetsCurrent","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Current Assets"}],"concept_label":"Cash and Cash Equivalent","current_period_value":185.2,"prior_period_value":173.0,"visual_current_value":185.2,"visual_prior_value":173.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-69","text_snippet":"185.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-69","text_snippet":"173.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":185.2,"prior_value":173.0},{"tag":"us-gaap:CommonStockValue","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,1.0,0],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquity","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:StockholdersEquity","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Stockholders' Equity"}],"concept_label":"Common Stock, Value, Issued","current_period_value":164.7,"prior_period_value":164.7,"visual_current_value":164.7,"visual_prior_value":164.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementClassOfStockAxis=aos:CommonStockClassUndefinedMember","dimensions":[{"axis":"us-gaap:StatementClassOfStockAxis","axis_label":"Statement Class Of Stock","member":"aos:CommonStockClassUndefinedMember","member_label":"Common Stock"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-9","char_anchor":"f-125","text_snippet":"164.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-9","char_anchor":"f-125","text_snippet":"164.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":164.7,"prior_value":164.7},{"tag":"us-gaap:CommonStockValue","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,1.0,0],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquity","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:StockholdersEquity","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Stockholders' Equity"}],"concept_label":"Common Stock, Value, Issued","current_period_value":130,"prior_period_value":130.0,"visual_current_value":130,"visual_prior_value":130.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementClassOfStockAxis=us-gaap:CommonClassAMember","dimensions":[{"axis":"us-gaap:StatementClassOfStockAxis","axis_label":"Statement Class Of Stock","member":"us-gaap:CommonClassAMember","member_label":"Common Class A"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-7","char_anchor":"f-121","text_snippet":"130.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-7","char_anchor":"f-121","text_snippet":"130.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":130,"prior_value":130.0},{"tag":"us-gaap:EmployeeRelatedLiabilitiesCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrentAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0,2.0,1],"section_concept":"us-gaap:LiabilitiesCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrent","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesCurrent","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Current Liabilities"}],"concept_label":"Employee-related Liabilities, Current","current_period_value":60.7,"prior_period_value":62.7,"visual_current_value":60.7,"visual_prior_value":62.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-99","text_snippet":"60.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-99","text_snippet":"62.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":60.7,"prior_value":62.7},{"tag":"us-gaap:IntangibleAssetsNetExcludingGoodwill","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":6.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Assets","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Assets","calculation_weight":1.0,"calculation_order":4.0,"section_label":null}],"concept_label":"Intangible Assets, Net (Excluding Goodwill)","current_period_value":598.7,"prior_period_value":373.9,"visual_current_value":598.7,"visual_prior_value":373.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-89","text_snippet":"598.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-89","text_snippet":"373.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":598.7,"prior_value":373.9},{"tag":"us-gaap:Liabilities","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAndStockholdersEquity","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesAndStockholdersEquity","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Liabilities","current_period_value":1772.4,"prior_period_value":1412.6,"visual_current_value":1772.4,"visual_prior_value":1412.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-117","text_snippet":"1,772.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-117","text_snippet":"1,412.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":1772.4,"prior_value":1412.6},{"tag":"us-gaap:LiabilitiesAndStockholdersEquity","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StatementLineItems","order":4.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Liabilities and Equity","current_period_value":3650.3,"prior_period_value":3267.7,"visual_current_value":3650.3,"visual_prior_value":3267.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-137","text_snippet":"3,650.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-137","text_snippet":"3,267.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":3650.3,"prior_value":3267.7},{"tag":"us-gaap:LiabilitiesCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrentAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0,6.0,5],"section_concept":"us-gaap:LiabilitiesCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Liabilities","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Liabilities","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Current Liabilities"}],"concept_label":"Liabilities, Current","current_period_value":878.1,"prior_period_value":882.1,"visual_current_value":878.1,"visual_prior_value":882.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-107","text_snippet":"878.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-107","text_snippet":"882.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":878.1,"prior_value":882.1},{"tag":"us-gaap:LongTermDebtCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrentAbstract","order":5.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0,5.0,4],"section_concept":"us-gaap:LiabilitiesCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrent","weight":1.0,"order":5.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesCurrent","calculation_weight":1.0,"calculation_order":5.0,"section_label":"Current Liabilities"}],"concept_label":"Long-Term Debt, Current Maturities","current_period_value":41.6,"prior_period_value":10.0,"visual_current_value":41.6,"visual_prior_value":10.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-105","text_snippet":"41.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-105","text_snippet":"10.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":41.6,"prior_value":10.0},{"tag":"us-gaap:LongTermDebtNoncurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Liabilities","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Liabilities","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Long-Term Debt, Excluding Current Maturities","current_period_value":574.2,"prior_period_value":259.8,"visual_current_value":574.2,"visual_prior_value":259.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-109","text_snippet":"574.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-109","text_snippet":"259.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":574.2,"prior_value":259.8},{"tag":"us-gaap:MarketableSecuritiesCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrentAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0,2.0,1],"section_concept":"us-gaap:AssetsCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrent","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:AssetsCurrent","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Current Assets"}],"concept_label":"Marketable Securities, Current","current_period_value":18.7,"prior_period_value":27.2,"visual_current_value":18.7,"visual_prior_value":27.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-71","text_snippet":"18.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-71","text_snippet":"27.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":18.7,"prior_value":27.2},{"tag":"us-gaap:OperatingLeaseLiabilityNoncurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAbstract","order":4.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Liabilities","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Liabilities","calculation_weight":1.0,"calculation_order":4.0,"section_label":null}],"concept_label":"Operating Lease, Liability, Noncurrent","current_period_value":40.7,"prior_period_value":25.2,"visual_current_value":40.7,"visual_prior_value":25.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-113","text_snippet":"40.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-113","text_snippet":"25.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":40.7,"prior_value":25.2},{"tag":"us-gaap:OperatingLeaseRightOfUseAsset","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":7.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,7.0,6],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Assets","weight":1.0,"order":5.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Assets","calculation_weight":1.0,"calculation_order":5.0,"section_label":null}],"concept_label":"Operating Lease, Right-of-Use Asset","current_period_value":51.8,"prior_period_value":34.6,"visual_current_value":51.8,"visual_prior_value":34.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-91","text_snippet":"51.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-91","text_snippet":"34.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":51.8,"prior_value":34.6},{"tag":"us-gaap:OtherAssetsCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrentAbstract","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0,5.0,4],"section_concept":"us-gaap:AssetsCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrent","weight":1.0,"order":5.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:AssetsCurrent","calculation_weight":1.0,"calculation_order":5.0,"section_label":"Current Assets"}],"concept_label":"Other Assets, Current","current_period_value":41.9,"prior_period_value":47.8,"visual_current_value":41.9,"visual_prior_value":47.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-77","text_snippet":"41.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-77","text_snippet":"47.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":41.9,"prior_value":47.8},{"tag":"us-gaap:OtherAssetsNoncurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":8.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,8.0,7],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Assets","weight":1.0,"order":6.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Assets","calculation_weight":1.0,"calculation_order":6.0,"section_label":null}],"concept_label":"Other Assets, Noncurrent","current_period_value":79.3,"prior_period_value":95.6,"visual_current_value":79.3,"visual_prior_value":95.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-93","text_snippet":"79.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-93","text_snippet":"95.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":79.3,"prior_value":95.6},{"tag":"us-gaap:OtherLiabilitiesNoncurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAbstract","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Liabilities","weight":1.0,"order":5.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Liabilities","calculation_weight":1.0,"calculation_order":5.0,"section_label":null}],"concept_label":"Other Liabilities, Noncurrent","current_period_value":142.4,"prior_period_value":121.0,"visual_current_value":142.4,"visual_prior_value":121.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-115","text_snippet":"142.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-115","text_snippet":"121.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":142.4,"prior_value":121.0},{"tag":"us-gaap:ProductWarrantyAccrualClassifiedCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrentAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0,4.0,3],"section_concept":"us-gaap:LiabilitiesCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesCurrent","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:LiabilitiesCurrent","calculation_weight":1.0,"calculation_order":4.0,"section_label":"Current Liabilities"}],"concept_label":"Product Warranty Accrual, Current","current_period_value":73.4,"prior_period_value":69.8,"visual_current_value":73.4,"visual_prior_value":69.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-103","text_snippet":"73.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-103","text_snippet":"69.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":73.4,"prior_value":69.8},{"tag":"us-gaap:ProductWarrantyAccrualNoncurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:LiabilitiesAbstract","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Liabilities","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Liabilities","calculation_weight":1.0,"calculation_order":3.0,"section_label":null}],"concept_label":"Product Warranty Accrual, Noncurrent","current_period_value":137,"prior_period_value":124.5,"visual_current_value":137,"visual_prior_value":124.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-111","text_snippet":"137.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-111","text_snippet":"124.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":137,"prior_value":124.5},{"tag":"us-gaap:PropertyPlantAndEquipmentGross","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:PropertyPlantAndEquipmentNet","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:PropertyPlantAndEquipmentNet","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Property, Plant and Equipment, Gross","current_period_value":1579.8,"prior_period_value":1517.8,"visual_current_value":1579.8,"visual_prior_value":1517.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-81","text_snippet":"1,579.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-81","text_snippet":"1,517.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":1579.8,"prior_value":1517.8},{"tag":"us-gaap:PropertyPlantAndEquipmentNet","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":4.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:Assets","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:Assets","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Property, Plant and Equipment, Net","current_period_value":632.2,"prior_period_value":634.4,"visual_current_value":632.2,"visual_prior_value":634.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-85","text_snippet":"632.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-85","text_snippet":"634.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":632.2,"prior_value":634.4},{"tag":"us-gaap:ReceivablesNetCurrent","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrentAbstract","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0,3.0,2],"section_concept":"us-gaap:AssetsCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrent","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:AssetsCurrent","calculation_weight":1.0,"calculation_order":3.0,"section_label":"Current Assets"}],"concept_label":"Receivables, Net, Current","current_period_value":634.1,"prior_period_value":641.5,"visual_current_value":634.1,"visual_prior_value":641.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-73","text_snippet":"634.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-73","text_snippet":"641.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":634.1,"prior_value":641.5},{"tag":"us-gaap:RetainedEarningsAccumulatedDeficit","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,3.0,2],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquity","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:StockholdersEquity","calculation_weight":1.0,"calculation_order":3.0,"section_label":"Stockholders' Equity"}],"concept_label":"Retained Earnings (Accumulated Deficit)","current_period_value":4019.8,"prior_period_value":3688.8,"visual_current_value":4019.8,"visual_prior_value":3688.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-129","text_snippet":"4,019.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-129","text_snippet":"3,688.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":4019.8,"prior_value":3688.8},{"tag":"us-gaap:TreasuryStockValue","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquityAbstract","order":5.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2,5.0,4],"section_concept":"us-gaap:StockholdersEquityAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:StockholdersEquity","weight":-1.0,"order":5.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:StockholdersEquity","calculation_weight":-1.0,"calculation_order":5.0,"section_label":"Stockholders' Equity"}],"concept_label":"Treasury Stock, Value","current_period_value":2954.9,"prior_period_value":2623.9,"visual_current_value":-2954.9,"visual_prior_value":-2623.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-133","text_snippet":"2,954.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-133","text_snippet":"2,623.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-2954.9,"prior_value":-2623.9},{"tag":"us-gaap:CommonStockSharesIssued","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheetsparenthetical","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheetsparenthetical","parent":"us-gaap:StatementLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Common Stock, Shares, Issued","current_period_value":164714053,"prior_period_value":164707143.0,"visual_current_value":164714053,"visual_prior_value":164707143.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementClassOfStockAxis=aos:CommonStockClassUndefinedMember","dimensions":[{"axis":"us-gaap:StatementClassOfStockAxis","axis_label":"Statement Class Of Stock","member":"aos:CommonStockClassUndefinedMember","member_label":"Common Stock"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-9","char_anchor":"f-123","text_snippet":"164,714,053","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-9","char_anchor":"f-123","text_snippet":"164,707,143","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":164714053,"prior_value":164707143.0},{"tag":"us-gaap:CommonStockSharesIssued","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheetsparenthetical","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheetsparenthetical","parent":"us-gaap:StatementLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Common Stock, Shares, Issued","current_period_value":25993539,"prior_period_value":26000449.0,"visual_current_value":25993539,"visual_prior_value":26000449.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementClassOfStockAxis=us-gaap:CommonClassAMember","dimensions":[{"axis":"us-gaap:StatementClassOfStockAxis","axis_label":"Statement Class Of Stock","member":"us-gaap:CommonClassAMember","member_label":"Common Class A"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-7","char_anchor":"f-119","text_snippet":"25,993,539","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-7","char_anchor":"f-119","text_snippet":"26,000,449","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":25993539,"prior_value":26000449.0},{"tag":"us-gaap:InventoryNet","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets|inventoriesdetails","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrentAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0,4.0,3],"section_concept":"us-gaap:AssetsCurrentAbstract","calculation_relationships":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsCurrent","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedbalancesheets","calculation_parent":"us-gaap:AssetsCurrent","calculation_weight":1.0,"calculation_order":4.0,"section_label":"Current Assets"},{"role":"inventoriesdetails","parent":"us-gaap:InventoryDisclosureAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,6.0,5],"section_concept":null,"section_label":null}],"concept_label":"Inventory, Net","current_period_value":488.5,"prior_period_value":532.6,"visual_current_value":488.5,"visual_prior_value":532.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-75","text_snippet":"488.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-75","text_snippet":"532.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":488.5,"prior_value":532.6},{"tag":"us-gaap:Assets","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":9.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,9.0,8],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Assets","current_period_value":3650.3,"prior_period_value":null,"visual_current_value":3650.3,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-95","text_snippet":"3,650.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":3650.3,"prior_value":null},{"tag":"us-gaap:Assets","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":9.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,9.0,8],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Assets","current_period_value":2858.8,"prior_period_value":null,"visual_current_value":2858.8,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-104","char_anchor":"f-482","text_snippet":"2,858.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":2858.8,"prior_value":null},{"tag":"us-gaap:Assets","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":9.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,9.0,8],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Assets","current_period_value":532.7,"prior_period_value":null,"visual_current_value":532.7,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-106","char_anchor":"f-484","text_snippet":"532.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":532.7,"prior_value":null},{"tag":"us-gaap:Assets","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":9.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,9.0,8],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Assets","current_period_value":3391.5,"prior_period_value":null,"visual_current_value":3391.5,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-108","char_anchor":"f-486","text_snippet":"3,391.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":3391.5,"prior_value":null},{"tag":"us-gaap:Assets","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedbalancesheets|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedbalancesheets","parent":"us-gaap:AssetsAbstract","order":9.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,9.0,8],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Assets","current_period_value":258.8,"prior_period_value":null,"visual_current_value":258.8,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:ConsolidationItemsAxis=us-gaap:CorporateNonSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:CorporateNonSegmentMember","member_label":"Corporate Non Segment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-110","char_anchor":"f-488","text_snippet":"258.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":258.8,"prior_value":null},{"tag":"aos:PaymentsForProceedsFromStockOptionsActivity","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","order":4.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,3.0,2,4.0,3],"section_concept":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","weight":-1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","calculation_weight":-1.0,"calculation_order":4.0,"section_label":"Financing Activities"}],"concept_label":"Payments For (Proceeds From) Stock Options Activity","current_period_value":0.5,"prior_period_value":1.8,"visual_current_value":-0.5,"visual_prior_value":-1.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-169","text_snippet":"0.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-170","text_snippet":"1.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-0.5,"prior_value":-1.8},{"tag":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents","date_type":"Q","period_type":"instant","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:StatementOfCashFlowsAbstract","order":6.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,6.0,5],"section_concept":null,"section_label":null}],"concept_label":"Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation","current_period_value":185.2,"prior_period_value":173.0,"visual_current_value":185.2,"visual_prior_value":173.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-181","text_snippet":"185.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-12","char_anchor":"f-182","text_snippet":"173.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":185.2,"prior_value":173.0},{"tag":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:StatementOfCashFlowsAbstract","order":5.0,"preferred_label_role":"totalLabel","global_sort_position":[0,5.0,4],"section_concept":null,"section_label":null}],"concept_label":"Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation","current_period_value":10.7,"prior_period_value":-66.6,"visual_current_value":10.7,"visual_prior_value":-66.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-177","text_snippet":"10.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-178","text_snippet":"66.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":10.7,"prior_value":-66.6},{"tag":"us-gaap:DeferredIncomeTaxesAndTaxCredits","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,3.0,2],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":6.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":6.0,"section_label":"Operating Activities"}],"concept_label":"Deferred Income Taxes and Tax Credits","current_period_value":18.3,"prior_period_value":-5.0,"visual_current_value":18.3,"visual_prior_value":-5.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-145","text_snippet":"18.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-146","text_snippet":"5.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":18.3,"prior_value":-5.0},{"tag":"us-gaap:EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:StatementOfCashFlowsAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation","current_period_value":0.5,"prior_period_value":0.6,"visual_current_value":0.5,"visual_prior_value":0.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-175","text_snippet":"0.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-176","text_snippet":"0.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.5,"prior_value":0.6},{"tag":"us-gaap:IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:IncreaseDecreaseInOperatingCapitalAbstract","order":1.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,2.0,1,4.0,3,1.0,0],"section_concept":"us-gaap:IncreaseDecreaseInOperatingCapitalAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":-1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":-1.0,"calculation_order":4.0,"section_label":"Operating Activities"}],"concept_label":"Increase (Decrease) in Other Current Assets and Liabilities, Net","current_period_value":43.2,"prior_period_value":125.3,"visual_current_value":-43.2,"visual_prior_value":-125.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-147","text_snippet":"43.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-148","text_snippet":"125.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-43.2,"prior_value":-125.3},{"tag":"us-gaap:IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:IncreaseDecreaseInOperatingCapitalAbstract","order":2.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,2.0,1,4.0,3,2.0,1],"section_concept":"us-gaap:IncreaseDecreaseInOperatingCapitalAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":-1.0,"order":5.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":-1.0,"calculation_order":5.0,"section_label":"Operating Activities"}],"concept_label":"Increase (Decrease) in Other Noncurrent Assets and Liabilities, Net","current_period_value":-5.8,"prior_period_value":-5.6,"visual_current_value":5.8,"visual_prior_value":5.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-149","text_snippet":"5.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-150","text_snippet":"5.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":5.8,"prior_value":5.6},{"tag":"us-gaap:NetCashProvidedByUsedInFinancingActivities","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,3.0,2,6.0,5],"section_concept":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Financing Activities"}],"concept_label":"Cash Provided by (Used in) Financing Activity, Including Discontinued Operation","current_period_value":361.3,"prior_period_value":-95.1,"visual_current_value":361.3,"visual_prior_value":-95.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-173","text_snippet":"361.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-174","text_snippet":"95.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":361.3,"prior_value":-95.1},{"tag":"us-gaap:NetCashProvidedByUsedInInvestingActivities","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","order":5.0,"preferred_label_role":"totalLabel","global_sort_position":[0,2.0,1,5.0,4],"section_concept":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","calculation_weight":1.0,"calculation_order":4.0,"section_label":"Investing Activities"}],"concept_label":"Cash Provided by (Used in) Investing Activity, Including Discontinued Operation","current_period_value":-480.5,"prior_period_value":-10.8,"visual_current_value":-480.5,"visual_prior_value":-10.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-161","text_snippet":"480.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-162","text_snippet":"10.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-480.5,"prior_value":-10.8},{"tag":"us-gaap:NetCashProvidedByUsedInOperatingActivities","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","calculation_weight":1.0,"calculation_order":3.0,"section_label":"Operating Activities"}],"concept_label":"Cash Provided by (Used in) Operating Activity, Including Discontinued Operation","current_period_value":129.4,"prior_period_value":38.7,"visual_current_value":129.4,"visual_prior_value":38.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-151","text_snippet":"129.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-152","text_snippet":"38.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":129.4,"prior_value":38.7,"scope_status":"mixed_scope_warning","scope_warning":"Operating cash flow is reported as consolidated cash flow while the filing also discloses discontinued operations or wind-down activity (Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation). Do not divide this consolidated CFO by continuing-operations revenue without an adjustment.","scope_bridge_ids":["cash_flow_scope_bridge:operating_cash_flow:2026-Q1:direct_discontinued"]},{"tag":"us-gaap:PaymentsForRepurchaseOfCommonStock","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","order":3.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,3.0,2,3.0,2],"section_concept":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","weight":-1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","calculation_weight":-1.0,"calculation_order":3.0,"section_label":"Financing Activities"}],"concept_label":"Payments for Repurchase of Common Stock","current_period_value":51.3,"prior_period_value":120.6,"visual_current_value":-51.3,"visual_prior_value":-120.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-167","text_snippet":"51.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-168","text_snippet":"120.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-51.3,"prior_value":-120.6},{"tag":"us-gaap:PaymentsOfDividendsCommonStock","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","order":5.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,3.0,2,5.0,4],"section_concept":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","weight":-1.0,"order":5.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","calculation_weight":-1.0,"calculation_order":5.0,"section_label":"Financing Activities"}],"concept_label":"Payments of Ordinary Dividends, Common Stock","current_period_value":50.2,"prior_period_value":49.2,"visual_current_value":-50.2,"visual_prior_value":-49.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-171","text_snippet":"50.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-172","text_snippet":"49.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-50.2,"prior_value":-49.2},{"tag":"us-gaap:ProceedsFromIssuanceOfLongTermDebt","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,3.0,2,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Financing Activities"}],"concept_label":"Proceeds from Issuance of Long-Term Debt","current_period_value":564.4,"prior_period_value":240.5,"visual_current_value":564.4,"visual_prior_value":240.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-163","text_snippet":"564.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-164","text_snippet":"240.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":564.4,"prior_value":240.5},{"tag":"us-gaap:RepaymentsOfLongTermDebt","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","order":2.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,3.0,2,2.0,1],"section_concept":"us-gaap:NetCashProvidedByUsedInFinancingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInFinancingActivities","calculation_weight":-1.0,"calculation_order":2.0,"section_label":"Financing Activities"}],"concept_label":"Repayments of Long-Term Debt","current_period_value":101.1,"prior_period_value":164.0,"visual_current_value":-101.1,"visual_prior_value":-164.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-165","text_snippet":"101.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-166","text_snippet":"164.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-101.1,"prior_value":-164.0},{"tag":"us-gaap:NetIncomeLoss","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|condensedconsolidatedstatementsofcomprehensiveearnings|condensedconsolidatedstatementsofearnings|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":8.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,8.0,7],"section_concept":null,"section_label":null},{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":9.0,"preferred_label_role":"totalLabel","global_sort_position":[0,9.0,8],"section_concept":null,"section_label":null},{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:StatementOfIncomeAndComprehensiveIncomeAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:ComprehensiveIncomeNetOfTax","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","calculation_parent":"us-gaap:ComprehensiveIncomeNetOfTax","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Operating Activities"}],"concept_label":"Net Income (Loss) Attributable to Parent","current_period_value":118,"prior_period_value":136.6,"visual_current_value":118,"visual_prior_value":136.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-47","text_snippet":"118.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-48","text_snippet":"136.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":118,"prior_value":136.6},{"tag":"us-gaap:NetIncomeLoss","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|condensedconsolidatedstatementsofcomprehensiveearnings|condensedconsolidatedstatementsofearnings|condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":8.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,8.0,7],"section_concept":null,"section_label":null},{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":9.0,"preferred_label_role":"totalLabel","global_sort_position":[0,9.0,8],"section_concept":null,"section_label":null},{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:StatementOfIncomeAndComprehensiveIncomeAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:ComprehensiveIncomeNetOfTax","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","calculation_parent":"us-gaap:ComprehensiveIncomeNetOfTax","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Operating Activities"}],"concept_label":"Net Income (Loss) Attributable to Parent","current_period_value":118,"prior_period_value":136.6,"visual_current_value":118,"visual_prior_value":136.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:RetainedEarningsMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:RetainedEarningsMember","member_label":"Retained Earnings"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-33","char_anchor":"f-213","text_snippet":"118.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-34","char_anchor":"f-214","text_snippet":"136.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":118,"prior_value":136.6},{"tag":"us-gaap:DepreciationDepletionAndAmortization","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Operating Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Depreciation, Depletion and Amortization","current_period_value":23.9,"prior_period_value":20.7,"visual_current_value":23.9,"visual_prior_value":20.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-141","text_snippet":"23.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-142","text_snippet":"20.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":23.9,"prior_value":20.7},{"tag":"us-gaap:DepreciationDepletionAndAmortization","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Operating Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Depreciation, Depletion and Amortization","current_period_value":0.3,"prior_period_value":0.3,"visual_current_value":0.3,"visual_prior_value":0.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:CorporateNonSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:CorporateNonSegmentMember","member_label":"Corporate Non Segment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-93","char_anchor":"f-498","text_snippet":"0.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-100","char_anchor":"f-499","text_snippet":"0.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.3,"prior_value":0.3},{"tag":"us-gaap:DepreciationDepletionAndAmortization","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Operating Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Depreciation, Depletion and Amortization","current_period_value":23.6,"prior_period_value":20.4,"visual_current_value":23.6,"visual_prior_value":20.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-496","text_snippet":"23.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-497","text_snippet":"20.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":23.6,"prior_value":20.4},{"tag":"us-gaap:DepreciationDepletionAndAmortization","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Operating Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Depreciation, Depletion and Amortization","current_period_value":19.1,"prior_period_value":15.4,"visual_current_value":19.1,"visual_prior_value":15.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-492","text_snippet":"19.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-493","text_snippet":"15.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":19.1,"prior_value":15.4},{"tag":"us-gaap:DepreciationDepletionAndAmortization","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Operating Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Depreciation, Depletion and Amortization","current_period_value":4.5,"prior_period_value":5.0,"visual_current_value":4.5,"visual_prior_value":5.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-494","text_snippet":"4.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-495","text_snippet":"5.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":4.5,"prior_value":5.0},{"tag":"us-gaap:PaymentsToAcquireProductiveAssets","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","order":1.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","weight":-1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","calculation_weight":-1.0,"calculation_order":4.0,"section_label":"Investing Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Payments to Acquire Productive Assets","current_period_value":10.5,"prior_period_value":21.3,"visual_current_value":-10.5,"visual_prior_value":-21.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-153","text_snippet":"10.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-154","text_snippet":"21.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-10.5,"prior_value":-21.3},{"tag":"us-gaap:PaymentsToAcquireProductiveAssets","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","order":1.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","weight":-1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","calculation_weight":-1.0,"calculation_order":4.0,"section_label":"Investing Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Payments to Acquire Productive Assets","current_period_value":10.5,"prior_period_value":21.3,"visual_current_value":-10.5,"visual_prior_value":-21.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-506","text_snippet":"10.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-507","text_snippet":"21.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-10.5,"prior_value":-21.3},{"tag":"us-gaap:PaymentsToAcquireProductiveAssets","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","order":1.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","weight":-1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","calculation_weight":-1.0,"calculation_order":4.0,"section_label":"Investing Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Payments to Acquire Productive Assets","current_period_value":9.5,"prior_period_value":19.0,"visual_current_value":-9.5,"visual_prior_value":-19.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-502","text_snippet":"9.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-503","text_snippet":"19.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-9.5,"prior_value":-19.0},{"tag":"us-gaap:PaymentsToAcquireProductiveAssets","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","order":1.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,2.0,1,1.0,0],"section_concept":"us-gaap:NetCashProvidedByUsedInInvestingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","weight":-1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInInvestingActivities","calculation_weight":-1.0,"calculation_order":4.0,"section_label":"Investing Activities"},{"role":"segmentresultsscheduleofassetsdepreciationandcapitalexpenditurebysegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Payments to Acquire Productive Assets","current_period_value":1,"prior_period_value":2.3,"visual_current_value":-1,"visual_prior_value":-2.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-504","text_snippet":"1.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-505","text_snippet":"2.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-1,"prior_value":-2.3},{"tag":"us-gaap:AllocatedShareBasedCompensationExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|sharebasedcompensationnarrativedetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":3.0,"section_label":"Operating Activities"},{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,5.0,4],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Payment Arrangement, Expense","current_period_value":6.6,"prior_period_value":6.1,"visual_current_value":6.6,"visual_prior_value":6.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-143","text_snippet":"6.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-144","text_snippet":"6.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":6.6,"prior_value":6.1},{"tag":"us-gaap:AllocatedShareBasedCompensationExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|sharebasedcompensationnarrativedetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":3.0,"section_label":"Operating Activities"},{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,5.0,4],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Payment Arrangement, Expense","current_period_value":0.9,"prior_period_value":0.5,"visual_current_value":0.9,"visual_prior_value":0.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-361","text_snippet":"0.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-87","char_anchor":"f-362","text_snippet":"0.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":0.9,"prior_value":0.5},{"tag":"us-gaap:AllocatedShareBasedCompensationExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcashflows|sharebasedcompensationnarrativedetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1],"section_concept":"us-gaap:NetCashProvidedByUsedInOperatingActivitiesAbstract","calculation_relationships":[{"role":"condensedconsolidatedstatementsofcashflows","parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofcashflows","calculation_parent":"us-gaap:NetCashProvidedByUsedInOperatingActivities","calculation_weight":1.0,"calculation_order":3.0,"section_label":"Operating Activities"},{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,5.0,4],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Payment Arrangement, Expense","current_period_value":5.7,"prior_period_value":5.5,"visual_current_value":5.7,"visual_prior_value":5.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-80","char_anchor":"f-342","text_snippet":"5.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-81","char_anchor":"f-343","text_snippet":"5.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":5.7,"prior_value":5.5},{"tag":"us-gaap:ComprehensiveIncomeNetOfTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:StatementOfIncomeAndComprehensiveIncomeAbstract","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Comprehensive Income (Loss), Net of Tax, Attributable to Parent","current_period_value":115.9,"prior_period_value":138.2,"visual_current_value":115.9,"visual_prior_value":138.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-67","text_snippet":"115.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-68","text_snippet":"138.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":115.9,"prior_value":138.2},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,2.0,1,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:ComprehensiveIncomeNetOfTax","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","calculation_parent":"us-gaap:ComprehensiveIncomeNetOfTax","calculation_weight":1.0,"calculation_order":3.0,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax","current_period_value":1.3,"prior_period_value":0.8,"visual_current_value":1.3,"visual_prior_value":0.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-61","text_snippet":"1.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-62","text_snippet":"0.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":1.3,"prior_value":0.8},{"tag":"us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract","order":3.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,2.0,1,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:ComprehensiveIncomeNetOfTax","weight":-1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","calculation_parent":"us-gaap:ComprehensiveIncomeNetOfTax","calculation_weight":-1.0,"calculation_order":4.0,"section_label":null}],"concept_label":"Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax","current_period_value":-0.1,"prior_period_value":-0.1,"visual_current_value":0.1,"visual_prior_value":0.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-65","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-66","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.1,"prior_value":0.1},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcomprehensiveearningsparenthetical","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcomprehensiveearningsparenthetical","parent":"us-gaap:StatementOfIncomeAndComprehensiveIncomeAbstract","order":1.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax","current_period_value":0.4,"prior_period_value":0.3,"visual_current_value":-0.4,"visual_prior_value":-0.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-59","text_snippet":"0.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-60","text_snippet":"0.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-0.4,"prior_value":-0.3},{"tag":"us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcomprehensiveearningsparenthetical","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcomprehensiveearningsparenthetical","parent":"us-gaap:StatementOfIncomeAndComprehensiveIncomeAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax","current_period_value":0,"prior_period_value":0.0,"visual_current_value":0,"visual_prior_value":0.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-63","text_snippet":"0.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-64","text_snippet":"0.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":0,"prior_value":0.0},{"tag":"us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcomprehensiveearnings|derivativeinstrumentsnarrativedetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,2.0,1,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:ComprehensiveIncomeNetOfTax","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","calculation_parent":"us-gaap:ComprehensiveIncomeNetOfTax","calculation_weight":1.0,"calculation_order":2.0,"section_label":null},{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":6.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,6.0,5],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax","current_period_value":-3.5,"prior_period_value":0.7,"visual_current_value":-3.5,"visual_prior_value":0.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-57","text_snippet":"3.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-58","text_snippet":"0.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-3.5,"prior_value":0.7},{"tag":"us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofcomprehensiveearnings|derivativeinstrumentsnarrativedetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,2.0,1,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofcomprehensiveearnings","parent":"us-gaap:ComprehensiveIncomeNetOfTax","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofcomprehensiveearnings","calculation_parent":"us-gaap:ComprehensiveIncomeNetOfTax","calculation_weight":1.0,"calculation_order":2.0,"section_label":null},{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":6.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,6.0,5],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax","current_period_value":-2.8,"prior_period_value":-1.2,"visual_current_value":-2.8,"visual_prior_value":-1.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:StatementGeographicalAxis=us-gaap:NonUsMember|us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeForwardMember|us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap:NetInvestmentHedgingMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember","dimensions":[{"axis":"srt:StatementGeographicalAxis","axis_label":"Geography","member":"us-gaap:NonUsMember","member_label":"Non Us"},{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeForwardMember","member_label":"Foreign Exchange Forward"},{"axis":"us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis","axis_label":"Derivative Instruments Gain Loss By Hedging Relationship","member":"us-gaap:NetInvestmentHedgingMember","member_label":"Net Investment Hedging"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-141","char_anchor":"f-557","text_snippet":"2.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-142","char_anchor":"f-558","text_snippet":"1.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-2.8,"prior_value":-1.2},{"tag":"us-gaap:CommonStockDividendsPerShareCashPaid","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":12.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,12.0,11],"section_concept":null,"section_label":null}],"concept_label":"Common Stock, Dividends, Per Share, Cash Paid","current_period_value":0.36,"prior_period_value":0.34,"visual_current_value":0.36,"visual_prior_value":0.34,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-53","text_snippet":"0.36","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-54","text_snippet":"0.34","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":0.36,"prior_value":0.34},{"tag":"us-gaap:EarningsPerShareBasic","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":10.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,10.0,9],"section_concept":null,"section_label":null}],"concept_label":"Earnings Per Share, Basic","current_period_value":0.85,"prior_period_value":0.95,"visual_current_value":0.85,"visual_prior_value":0.95,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-49","text_snippet":"0.85","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-50","text_snippet":"0.95","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":0.85,"prior_value":0.95},{"tag":"us-gaap:EarningsPerShareDiluted","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":11.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,11.0,10],"section_concept":null,"section_label":null}],"concept_label":"Earnings Per Share, Diluted","current_period_value":0.85,"prior_period_value":0.95,"visual_current_value":0.85,"visual_prior_value":0.95,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-51","text_snippet":"0.85","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-52","text_snippet":"0.95","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":0.85,"prior_value":0.95},{"tag":"us-gaap:IncomeTaxExpenseBenefit","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":8.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,8.0,7],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:NetIncomeLoss","weight":-1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:NetIncomeLoss","calculation_weight":-1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Income Tax Expense (Benefit)","current_period_value":36.7,"prior_period_value":44.5,"visual_current_value":36.7,"visual_prior_value":44.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-45","text_snippet":"36.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-46","text_snippet":"44.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":36.7,"prior_value":44.5},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":945.6,"prior_period_value":963.9,"visual_current_value":945.6,"visual_prior_value":963.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-31","text_snippet":"945.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-32","text_snippet":"963.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":945.6,"prior_value":963.9},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":-8.5,"prior_period_value":-11.5,"visual_current_value":-8.5,"visual_prior_value":-11.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:IntersegmentEliminationMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:IntersegmentEliminationMember","member_label":"Intersegment Elimination"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-62","char_anchor":"f-261","text_snippet":"8.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-63","char_anchor":"f-262","text_snippet":"11.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-8.5,"prior_value":-11.5},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":-4.5,"prior_period_value":-5.3,"visual_current_value":-4.5,"visual_prior_value":-5.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:IntersegmentEliminationMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:IntersegmentEliminationMember","member_label":"Intersegment Elimination"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-94","char_anchor":"f-383","text_snippet":"4.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-101","char_anchor":"f-435","text_snippet":"5.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-4.5,"prior_value":-5.3},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":-4,"prior_period_value":-6.2,"visual_current_value":-4,"visual_prior_value":-6.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:IntersegmentEliminationMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:IntersegmentEliminationMember","member_label":"Intersegment Elimination"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-95","char_anchor":"f-384","text_snippet":"4.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-102","char_anchor":"f-436","text_snippet":"6.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-4,"prior_value":-6.2},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":954.1,"prior_period_value":975.4,"visual_current_value":954.1,"visual_prior_value":975.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-390","text_snippet":"954.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-442","text_snippet":"975.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":954.1,"prior_value":975.4},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":81.5,"prior_period_value":64.4,"visual_current_value":81.5,"visual_prior_value":64.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|srt:ProductOrServiceAxis=aos:BoilersRelatedPartsAndComponentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"srt:ProductOrServiceAxis","axis_label":"Product Lines","member":"aos:BoilersRelatedPartsAndComponentsMember","member_label":"Boilers, related parts, and components"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-50","char_anchor":"f-249","text_snippet":"81.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-51","char_anchor":"f-250","text_snippet":"64.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":81.5,"prior_value":64.4},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":611.8,"prior_period_value":624.6,"visual_current_value":611.8,"visual_prior_value":624.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|srt:ProductOrServiceAxis=aos:WaterHeatersAndRelatedPartsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"srt:ProductOrServiceAxis","axis_label":"Product Lines","member":"aos:WaterHeatersAndRelatedPartsMember","member_label":"Water heaters and related parts"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-48","char_anchor":"f-247","text_snippet":"611.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-49","char_anchor":"f-248","text_snippet":"624.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":611.8,"prior_value":624.6},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":60.1,"prior_period_value":59.7,"visual_current_value":60.1,"visual_prior_value":59.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|srt:ProductOrServiceAxis=aos:WaterTreatmentProductsAndRelatedPartsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"srt:ProductOrServiceAxis","axis_label":"Product Lines","member":"aos:WaterTreatmentProductsAndRelatedPartsMember","member_label":"Water treatment products and related parts"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-52","char_anchor":"f-251","text_snippet":"60.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-53","char_anchor":"f-252","text_snippet":"59.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":60.1,"prior_value":59.7},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":38.3,"prior_period_value":39.5,"visual_current_value":38.3,"visual_prior_value":39.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|srt:StatementGeographicalAxis=aos:AllOtherRestOfWorldMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"srt:StatementGeographicalAxis","axis_label":"Geography","member":"aos:AllOtherRestOfWorldMember","member_label":"All other Rest of World"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-58","char_anchor":"f-257","text_snippet":"38.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-59","char_anchor":"f-258","text_snippet":"39.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":38.3,"prior_value":39.5},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":162.4,"prior_period_value":187.2,"visual_current_value":162.4,"visual_prior_value":187.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|srt:StatementGeographicalAxis=country:CN|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"srt:StatementGeographicalAxis","axis_label":"Geography","member":"country:CN","member_label":"CN"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-56","char_anchor":"f-255","text_snippet":"162.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-57","char_anchor":"f-256","text_snippet":"187.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":162.4,"prior_value":187.2},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":753.4,"prior_period_value":748.7,"visual_current_value":753.4,"visual_prior_value":748.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-253","text_snippet":"753.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-254","text_snippet":"748.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":753.4,"prior_value":748.7},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":200.7,"prior_period_value":226.7,"visual_current_value":200.7,"visual_prior_value":226.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-259","text_snippet":"200.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-260","text_snippet":"226.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":200.7,"prior_value":226.7},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":748.9,"prior_period_value":743.4,"visual_current_value":748.9,"visual_prior_value":743.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-90","char_anchor":"f-378","text_snippet":"748.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-97","char_anchor":"f-430","text_snippet":"743.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":748.9,"prior_value":743.4},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":945.6,"prior_period_value":963.9,"visual_current_value":945.6,"visual_prior_value":963.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementBusinessSegmentsAxis=aos:ReportableSegmentsMember","dimensions":[{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:ReportableSegmentsMember","member_label":"Reportable Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-92","char_anchor":"f-380","text_snippet":"945.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-99","char_anchor":"f-432","text_snippet":"963.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":945.6,"prior_value":963.9},{"tag":"us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":1.0,"calculation_order":1.0,"section_label":null},{"role":"revenuerecognitionscheduleofsegmentsalesdisaggregatedbymajorproductlinedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Revenue from Contract with Customer, Excluding Assessed Tax","current_period_value":196.7,"prior_period_value":220.5,"visual_current_value":196.7,"visual_prior_value":220.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-91","char_anchor":"f-379","text_snippet":"196.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-98","char_anchor":"f-431","text_snippet":"220.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":196.7,"prior_value":220.5},{"tag":"us-gaap:CostOfGoodsAndServicesSold","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Cost of Product and Service Sold","current_period_value":579.9,"prior_period_value":588.5,"visual_current_value":579.9,"visual_prior_value":588.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-33","text_snippet":"579.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-34","text_snippet":"588.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":579.9,"prior_value":588.5},{"tag":"us-gaap:CostOfGoodsAndServicesSold","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Cost of Product and Service Sold","current_period_value":579.9,"prior_period_value":588.5,"visual_current_value":579.9,"visual_prior_value":588.5,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-405","text_snippet":"579.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-457","text_snippet":"588.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":579.9,"prior_value":588.5},{"tag":"us-gaap:CostOfGoodsAndServicesSold","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Cost of Product and Service Sold","current_period_value":451.7,"prior_period_value":445.7,"visual_current_value":451.7,"visual_prior_value":445.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-403","text_snippet":"451.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-455","text_snippet":"445.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":451.7,"prior_value":445.7},{"tag":"us-gaap:CostOfGoodsAndServicesSold","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:GrossProfit","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:GrossProfit","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Cost of Product and Service Sold","current_period_value":128.2,"prior_period_value":142.8,"visual_current_value":128.2,"visual_prior_value":142.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-404","text_snippet":"128.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-456","text_snippet":"142.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":128.2,"prior_value":142.8},{"tag":"us-gaap:GrossProfit","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":4.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":3.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":3.0,"section_label":null}],"concept_label":"Gross Profit","current_period_value":365.7,"prior_period_value":375.4,"visual_current_value":365.7,"visual_prior_value":375.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-35","text_snippet":"365.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-36","text_snippet":"375.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":365.7,"prior_value":375.4},{"tag":"us-gaap:GrossProfit","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":4.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":3.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":3.0,"section_label":null}],"concept_label":"Gross Profit","current_period_value":365.7,"prior_period_value":375.4,"visual_current_value":365.7,"visual_prior_value":375.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-410","text_snippet":"365.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-462","text_snippet":"375.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":365.7,"prior_value":375.4},{"tag":"us-gaap:GrossProfit","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":4.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":3.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":3.0,"section_label":null}],"concept_label":"Gross Profit","current_period_value":297.2,"prior_period_value":297.7,"visual_current_value":297.2,"visual_prior_value":297.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-408","text_snippet":"297.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-460","text_snippet":"297.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":297.2,"prior_value":297.7},{"tag":"us-gaap:GrossProfit","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":4.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":4.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":3.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":3.0,"section_label":null}],"concept_label":"Gross Profit","current_period_value":68.5,"prior_period_value":77.7,"visual_current_value":68.5,"visual_prior_value":77.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-409","text_snippet":"68.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-461","text_snippet":"77.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":68.5,"prior_value":77.7},{"tag":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":7.0,"preferred_label_role":"totalLabel","global_sort_position":[0,7.0,6],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:NetIncomeLoss","weight":1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:NetIncomeLoss","calculation_weight":1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":8.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,8.0,7],"section_concept":null,"section_label":null}],"concept_label":"Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest","current_period_value":154.7,"prior_period_value":181.1,"visual_current_value":154.7,"visual_prior_value":181.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-43","text_snippet":"154.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-44","text_snippet":"181.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":154.7,"prior_value":181.1},{"tag":"us-gaap:InterestExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":-1.0,"order":1.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":-1.0,"calculation_order":1.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":7.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,3.0,2,7.0,6],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":-1.0,"order":1.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":-1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Interest Expense, Operating and Nonoperating","current_period_value":7.1,"prior_period_value":2.9,"visual_current_value":7.1,"visual_prior_value":2.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-39","text_snippet":"7.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-40","text_snippet":"2.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":7.1,"prior_value":2.9},{"tag":"us-gaap:OtherNonoperatingIncomeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":6.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":3.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":5.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,3.0,2,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":1.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Other Nonoperating Income (Expense)","current_period_value":0.8,"prior_period_value":0.9,"visual_current_value":-0.8,"visual_prior_value":-0.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:CorporateNonSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:CorporateNonSegmentMember","member_label":"Corporate Non Segment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-93","char_anchor":"f-421","text_snippet":"0.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-100","char_anchor":"f-473","text_snippet":"0.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-0.8,"prior_value":-0.9},{"tag":"us-gaap:OtherNonoperatingIncomeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":6.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":3.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":5.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,3.0,2,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":1.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Other Nonoperating Income (Expense)","current_period_value":-0.8,"prior_period_value":0.3,"visual_current_value":0.8,"visual_prior_value":-0.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-420","text_snippet":"0.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-472","text_snippet":"0.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.8,"prior_value":-0.3},{"tag":"us-gaap:OtherNonoperatingIncomeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":6.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":3.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":5.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,3.0,2,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":1.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Other Nonoperating Income (Expense)","current_period_value":0.4,"prior_period_value":0.9,"visual_current_value":-0.4,"visual_prior_value":-0.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-418","text_snippet":"0.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-470","text_snippet":"0.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-0.4,"prior_value":-0.9},{"tag":"us-gaap:OtherNonoperatingIncomeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":6.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":3.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":3.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":5.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,3.0,2,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":1.0,"order":1.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Other Nonoperating Income (Expense)","current_period_value":-1.2,"prior_period_value":-0.6,"visual_current_value":1.2,"visual_prior_value":0.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-419","text_snippet":"1.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-471","text_snippet":"0.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":1.2,"prior_value":0.6},{"tag":"us-gaap:SellingGeneralAndAdministrativeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":-1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Selling, General and Administrative Expense","current_period_value":203.9,"prior_period_value":192.6,"visual_current_value":203.9,"visual_prior_value":192.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-37","text_snippet":"203.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-38","text_snippet":"192.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":203.9,"prior_value":192.6},{"tag":"us-gaap:SellingGeneralAndAdministrativeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":-1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Selling, General and Administrative Expense","current_period_value":26.8,"prior_period_value":21.8,"visual_current_value":26.8,"visual_prior_value":21.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:CorporateNonSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:CorporateNonSegmentMember","member_label":"Corporate Non Segment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-93","char_anchor":"f-416","text_snippet":"26.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-100","char_anchor":"f-468","text_snippet":"21.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":26.8,"prior_value":21.8},{"tag":"us-gaap:SellingGeneralAndAdministrativeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":-1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Selling, General and Administrative Expense","current_period_value":177.1,"prior_period_value":170.8,"visual_current_value":177.1,"visual_prior_value":170.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-415","text_snippet":"177.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-467","text_snippet":"170.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":177.1,"prior_value":170.8},{"tag":"us-gaap:SellingGeneralAndAdministrativeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":-1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Selling, General and Administrative Expense","current_period_value":122.2,"prior_period_value":113.4,"visual_current_value":122.2,"visual_prior_value":113.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-413","text_snippet":"122.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-465","text_snippet":"113.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":122.2,"prior_value":113.4},{"tag":"us-gaap:SellingGeneralAndAdministrativeExpense","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofearnings|segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeStatementAbstract","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"condensedconsolidatedstatementsofearnings","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":-1.0,"order":2.0}],"calculation_role":"condensedconsolidatedstatementsofearnings","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null},{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:OperatingIncomeLoss","weight":-1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:OperatingIncomeLoss","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Selling, General and Administrative Expense","current_period_value":54.9,"prior_period_value":57.4,"visual_current_value":54.9,"visual_prior_value":57.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-414","text_snippet":"54.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-466","text_snippet":"57.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":54.9,"prior_value":57.4},{"tag":"aos:AdjustmentsToAdditionalPaidInCapitalShareUnitsIssued","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":3.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Adjustments To Additional Paid In Capital, Share Units Issued","current_period_value":13.3,"prior_period_value":12.6,"visual_current_value":-13.3,"visual_prior_value":-12.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AdditionalPaidInCapitalMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AdditionalPaidInCapitalMember","member_label":"Additional Paid In Capital"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-27","char_anchor":"f-199","text_snippet":"13.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-28","char_anchor":"f-200","text_snippet":"12.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-13.3,"prior_value":-12.6},{"tag":"aos:ExciseTaxOnRepurchasesOfCommonStock","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":11.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,11.0,10],"section_concept":null,"section_label":null}],"concept_label":"Excise Tax On Repurchases Of Common Stock","current_period_value":0.5,"prior_period_value":1.2,"visual_current_value":-0.5,"visual_prior_value":-1.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:TreasuryStockCommonMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:TreasuryStockCommonMember","member_label":"Treasury Stock Common"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-41","char_anchor":"f-227","text_snippet":"0.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-42","char_anchor":"f-228","text_snippet":"1.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":-0.5,"prior_value":-1.2},{"tag":"aos:VestingOfShareUnits","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":4.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Vesting Of Share Units","current_period_value":4.3,"prior_period_value":1.7,"visual_current_value":-4.3,"visual_prior_value":-1.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AdditionalPaidInCapitalMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AdditionalPaidInCapitalMember","member_label":"Additional Paid In Capital"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-27","char_anchor":"f-201","text_snippet":"4.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-28","char_anchor":"f-202","text_snippet":"1.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-4.3,"prior_value":-1.7},{"tag":"aos:VestingOfShareUnits","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":4.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Vesting Of Share Units","current_period_value":-4.3,"prior_period_value":-1.7,"visual_current_value":4.3,"visual_prior_value":1.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:TreasuryStockCommonMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:TreasuryStockCommonMember","member_label":"Treasury Stock Common"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-41","char_anchor":"f-229","text_snippet":"4.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-42","char_anchor":"f-230","text_snippet":"1.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":4.3,"prior_value":1.7},{"tag":"us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,5.0,4],"section_concept":null,"section_label":null}],"concept_label":"APIC, Share-Based Payment Arrangement, Increase for Cost Recognition","current_period_value":6.3,"prior_period_value":6.0,"visual_current_value":6.3,"visual_prior_value":6.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AdditionalPaidInCapitalMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AdditionalPaidInCapitalMember","member_label":"Additional Paid In Capital"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-27","char_anchor":"f-203","text_snippet":"6.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-28","char_anchor":"f-204","text_snippet":"6.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":6.3,"prior_value":6.0},{"tag":"us-gaap:DividendsCommonStockCash","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":9.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,9.0,8],"section_concept":null,"section_label":null}],"concept_label":"Dividends, Common Stock, Cash","current_period_value":50,"prior_period_value":49.1,"visual_current_value":-50,"visual_prior_value":-49.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:RetainedEarningsMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:RetainedEarningsMember","member_label":"Retained Earnings"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-33","char_anchor":"f-215","text_snippet":"50.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-34","char_anchor":"f-216","text_snippet":"49.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-50,"prior_value":-49.1},{"tag":"us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":7.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,7.0,6],"section_concept":null,"section_label":null}],"concept_label":"Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture","current_period_value":13.3,"prior_period_value":12.6,"visual_current_value":13.3,"visual_prior_value":12.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AdditionalPaidInCapitalMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AdditionalPaidInCapitalMember","member_label":"Additional Paid In Capital"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-27","char_anchor":"f-207","text_snippet":"13.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-28","char_anchor":"f-208","text_snippet":"12.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":13.3,"prior_value":12.6},{"tag":"us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":6.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,6.0,5],"section_concept":null,"section_label":null}],"concept_label":"Stock Issued During Period, Value, Stock Options Exercised","current_period_value":2.6,"prior_period_value":0.1,"visual_current_value":2.6,"visual_prior_value":0.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:AdditionalPaidInCapitalMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:AdditionalPaidInCapitalMember","member_label":"Additional Paid In Capital"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-27","char_anchor":"f-205","text_snippet":"2.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-28","char_anchor":"f-206","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":2.6,"prior_value":0.1},{"tag":"us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":6.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,6.0,5],"section_concept":null,"section_label":null}],"concept_label":"Stock Issued During Period, Value, Stock Options Exercised","current_period_value":-3.1,"prior_period_value":-1.8,"visual_current_value":-3.1,"visual_prior_value":-1.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:TreasuryStockCommonMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:TreasuryStockCommonMember","member_label":"Treasury Stock Common"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-41","char_anchor":"f-223","text_snippet":"3.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-42","char_anchor":"f-224","text_snippet":"1.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-3.1,"prior_value":-1.8},{"tag":"us-gaap:TreasuryStockValueAcquiredCostMethod","date_type":"Q","period_type":"duration","presentation_role":"condensedconsolidatedstatementsofstockholdersequity","presentation_hierarchy":[{"role":"condensedconsolidatedstatementsofstockholdersequity","parent":"us-gaap:IncreaseDecreaseInStockholdersEquityRollForward","order":10.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0,10.0,9],"section_concept":null,"section_label":null}],"concept_label":"Treasury Stock, Value, Acquired, Cost Method","current_period_value":51.3,"prior_period_value":120.6,"visual_current_value":-51.3,"visual_prior_value":-120.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:StatementEquityComponentsAxis=us-gaap:TreasuryStockCommonMember","dimensions":[{"axis":"us-gaap:StatementEquityComponentsAxis","axis_label":"Equity Components","member":"us-gaap:TreasuryStockCommonMember","member_label":"Treasury Stock Common"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-41","char_anchor":"f-225","text_snippet":"51.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-42","char_anchor":"f-226","text_snippet":"120.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-51.3,"prior_value":-120.6},{"tag":"dei:CityAreaCode","date_type":"Q","period_type":"duration","presentation_role":"coverpage","presentation_hierarchy":[{"role":"coverpage","parent":"dei:DocumentInformationLineItems","order":13.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,13.0,12],"section_concept":null,"section_label":null}],"concept_label":"City Area Code","current_period_value":414,"prior_period_value":null,"visual_current_value":414,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-13","text_snippet":"414","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":null,"current_value":414,"prior_value":null},{"tag":"dei:DocumentFiscalYearFocus","date_type":"Q","period_type":"duration","presentation_role":"coverpage","presentation_hierarchy":[{"role":"coverpage","parent":"dei:DocumentInformationLineItems","order":29.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,29.0,28],"section_concept":null,"section_label":null}],"concept_label":"Document Fiscal Year Focus","current_period_value":2026,"prior_period_value":null,"visual_current_value":2026,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-30","text_snippet":"2026","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":null,"current_value":2026,"prior_value":null},{"tag":"dei:EntityCentralIndexKey","date_type":"Q","period_type":"duration","presentation_role":"coverpage","presentation_hierarchy":[{"role":"coverpage","parent":"dei:DocumentInformationLineItems","order":26.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,26.0,25],"section_concept":null,"section_label":null}],"concept_label":"Entity Central Index Key","current_period_value":91142,"prior_period_value":null,"visual_current_value":91142,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-27","text_snippet":"0000091142","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":null,"current_value":91142,"prior_value":null},{"tag":"us-gaap:DebtInstrumentInterestRateDuringPeriod","date_type":"Q","period_type":"duration","presentation_role":"debtdetails","presentation_hierarchy":[{"role":"debtdetails","parent":"us-gaap:LineOfCreditFacilityLineItems","order":8.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,8.0,7],"section_concept":null,"section_label":null}],"concept_label":"Debt Instrument, Interest Rate During Period","current_period_value":4.55,"prior_period_value":null,"visual_current_value":4.55,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:CreditFacilityAxis=us-gaap:SecuredDebtMember|us-gaap:LongtermDebtTypeAxis=us-gaap:LineOfCreditMember","dimensions":[{"axis":"us-gaap:CreditFacilityAxis","axis_label":"Credit Facility","member":"us-gaap:SecuredDebtMember","member_label":"Secured Debt"},{"axis":"us-gaap:LongtermDebtTypeAxis","axis_label":"Long-Term Debt Type","member":"us-gaap:LineOfCreditMember","member_label":"Line Of Credit"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-78","char_anchor":"f-325","text_snippet":"4.55","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"hundredths","current_value":4.55,"prior_value":null},{"tag":"us-gaap:DerivativeFairValueOfDerivativeAsset","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Derivative Asset, Subject to Master Netting Arrangement, before Offset","current_period_value":2,"prior_period_value":0.1,"visual_current_value":2,"visual_prior_value":0.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeContractMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeContractMember","member_label":"Foreign Exchange Contract"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-117","char_anchor":"f-520","text_snippet":"2.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-113","char_anchor":"f-512","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":2,"prior_value":0.1},{"tag":"us-gaap:DerivativeFixedInterestRate","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Fixed Interest Rate","current_period_value":8.25,"prior_period_value":8.25,"visual_current_value":8.25,"visual_prior_value":8.25,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:InterestRateSwapMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:InterestRateSwapMember","member_label":"Interest Rate Swap"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-136","char_anchor":"f-541","text_snippet":"8.25","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-131","char_anchor":"f-533","text_snippet":"8.25","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"hundredths","current_value":8.25,"prior_value":8.25},{"tag":"us-gaap:InterestRateDerivativeLiabilitiesAtFairValue","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,5.0,4],"section_concept":null,"section_label":null}],"concept_label":"Interest Rate Derivative Liabilities, at Fair Value","current_period_value":0.4,"prior_period_value":0.8,"visual_current_value":0.4,"visual_prior_value":0.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:InterestRateSwapMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:InterestRateSwapMember","member_label":"Interest Rate Swap"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-136","char_anchor":"f-542","text_snippet":"0.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-131","char_anchor":"f-534","text_snippet":"0.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.4,"prior_value":0.8},{"tag":"us-gaap:DerivativeNotionalAmount","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails|derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,3.0,2],"section_concept":null,"section_label":null},{"role":"derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","parent":"us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Notional Amount","current_period_value":65,"prior_period_value":null,"visual_current_value":65,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:CurrencyAxis=currency:CAD|us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeForwardMember|us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap:CashFlowHedgingMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember|us-gaap:PositionAxis=us-gaap:ShortMember","dimensions":[{"axis":"srt:CurrencyAxis","axis_label":"Currency","member":"currency:CAD","member_label":"CAD"},{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeForwardMember","member_label":"Foreign Exchange Forward"},{"axis":"us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis","axis_label":"Derivative Instruments Gain Loss By Hedging Relationship","member":"us-gaap:CashFlowHedgingMember","member_label":"Cash Flow Hedging"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"},{"axis":"us-gaap:PositionAxis","axis_label":"Position","member":"us-gaap:ShortMember","member_label":"Short"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-120","char_anchor":"f-524","text_snippet":"65.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":65,"prior_value":null},{"tag":"us-gaap:DerivativeNotionalAmount","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails|derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,3.0,2],"section_concept":null,"section_label":null},{"role":"derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","parent":"us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Notional Amount","current_period_value":12.7,"prior_period_value":null,"visual_current_value":12.7,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:CurrencyAxis=currency:EUR|us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeForwardMember|us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap:CashFlowHedgingMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember|us-gaap:PositionAxis=us-gaap:LongMember","dimensions":[{"axis":"srt:CurrencyAxis","axis_label":"Currency","member":"currency:EUR","member_label":"EUR"},{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeForwardMember","member_label":"Foreign Exchange Forward"},{"axis":"us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis","axis_label":"Derivative Instruments Gain Loss By Hedging Relationship","member":"us-gaap:CashFlowHedgingMember","member_label":"Cash Flow Hedging"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"},{"axis":"us-gaap:PositionAxis","axis_label":"Position","member":"us-gaap:LongMember","member_label":"Long"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-123","char_anchor":"f-527","text_snippet":"12.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":12.7,"prior_value":null},{"tag":"us-gaap:DerivativeNotionalAmount","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails|derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,3.0,2],"section_concept":null,"section_label":null},{"role":"derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","parent":"us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Notional Amount","current_period_value":13.3,"prior_period_value":null,"visual_current_value":13.3,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:CurrencyAxis=currency:MXN|us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeForwardMember|us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap:CashFlowHedgingMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember|us-gaap:PositionAxis=us-gaap:LongMember","dimensions":[{"axis":"srt:CurrencyAxis","axis_label":"Currency","member":"currency:MXN","member_label":"MXN"},{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeForwardMember","member_label":"Foreign Exchange Forward"},{"axis":"us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis","axis_label":"Derivative Instruments Gain Loss By Hedging Relationship","member":"us-gaap:CashFlowHedgingMember","member_label":"Cash Flow Hedging"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"},{"axis":"us-gaap:PositionAxis","axis_label":"Position","member":"us-gaap:LongMember","member_label":"Long"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-127","char_anchor":"f-531","text_snippet":"13.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":13.3,"prior_value":null},{"tag":"us-gaap:DerivativeNotionalAmount","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails|derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,3.0,2],"section_concept":null,"section_label":null},{"role":"derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","parent":"us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Notional Amount","current_period_value":26,"prior_period_value":null,"visual_current_value":26,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeForwardMember|us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap:CashFlowHedgingMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember|us-gaap:PositionAxis=us-gaap:LongMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeForwardMember","member_label":"Foreign Exchange Forward"},{"axis":"us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis","axis_label":"Derivative Instruments Gain Loss By Hedging Relationship","member":"us-gaap:CashFlowHedgingMember","member_label":"Cash Flow Hedging"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"},{"axis":"us-gaap:PositionAxis","axis_label":"Position","member":"us-gaap:LongMember","member_label":"Long"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-131","char_anchor":"f-535","text_snippet":"26.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":26,"prior_value":null},{"tag":"us-gaap:DerivativeNotionalAmount","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails|derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,3.0,2],"section_concept":null,"section_label":null},{"role":"derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","parent":"us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Notional Amount","current_period_value":65,"prior_period_value":null,"visual_current_value":65,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeForwardMember|us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap:CashFlowHedgingMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember|us-gaap:PositionAxis=us-gaap:ShortMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeForwardMember","member_label":"Foreign Exchange Forward"},{"axis":"us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis","axis_label":"Derivative Instruments Gain Loss By Hedging Relationship","member":"us-gaap:CashFlowHedgingMember","member_label":"Cash Flow Hedging"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"},{"axis":"us-gaap:PositionAxis","axis_label":"Position","member":"us-gaap:ShortMember","member_label":"Short"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-132","char_anchor":"f-536","text_snippet":"65.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"millions","current_value":65,"prior_value":null},{"tag":"us-gaap:DerivativeNotionalAmount","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails|derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,3.0,2],"section_concept":null,"section_label":null},{"role":"derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","parent":"us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Notional Amount","current_period_value":4.2,"prior_period_value":null,"visual_current_value":4.2,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:InterestRateSwapMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:InterestRateSwapMember","member_label":"Interest Rate Swap"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-136","char_anchor":"f-540","text_snippet":"4.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"billions","current_value":4.2,"prior_value":null},{"tag":"us-gaap:DerivativeNotionalAmount","date_type":"Q","period_type":"instant","presentation_role":"derivativeinstrumentsnarrativedetails|derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsnarrativedetails","parent":"us-gaap:TradingActivityGainsAndLossesLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,6.0,5,3.0,2],"section_concept":null,"section_label":null},{"role":"derivativeinstrumentsscheduleofcurrencyofforeigncurrencyforwardcontractsdetails","parent":"us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,6.0,5,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Derivative, Notional Amount","current_period_value":1.5,"prior_period_value":null,"visual_current_value":1.5,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:StatementGeographicalAxis=us-gaap:NonUsMember|us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeForwardMember|us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap:NetInvestmentHedgingMember|us-gaap:HedgingDesignationAxis=us-gaap:DesignatedAsHedgingInstrumentMember","dimensions":[{"axis":"srt:StatementGeographicalAxis","axis_label":"Geography","member":"us-gaap:NonUsMember","member_label":"Non Us"},{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeForwardMember","member_label":"Foreign Exchange Forward"},{"axis":"us-gaap:DerivativeInstrumentsGainLossByHedgingRelationshipAxis","axis_label":"Derivative Instruments Gain Loss By Hedging Relationship","member":"us-gaap:NetInvestmentHedgingMember","member_label":"Net Investment Hedging"},{"axis":"us-gaap:HedgingDesignationAxis","axis_label":"Hedging Designation","member":"us-gaap:DesignatedAsHedgingInstrumentMember","member_label":"Designated As Hedging Instrument"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-144","char_anchor":"f-560","text_snippet":"1.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"billions","current_value":1.5,"prior_value":null},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax","date_type":"Q","period_type":"duration","presentation_role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","parent":"us-gaap:DerivativeLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax","current_period_value":2.1,"prior_period_value":1.0,"visual_current_value":2.1,"visual_prior_value":1.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-553","text_snippet":"2.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-554","text_snippet":"1.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":2.1,"prior_value":1.0},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax","date_type":"Q","period_type":"duration","presentation_role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","parent":"us-gaap:DerivativeLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax","current_period_value":1.5,"prior_period_value":1.3,"visual_current_value":1.5,"visual_prior_value":1.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeContractMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeContractMember","member_label":"Foreign Exchange Contract"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-137","char_anchor":"f-545","text_snippet":"1.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-138","char_anchor":"f-546","text_snippet":"1.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":1.5,"prior_value":1.3},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax","date_type":"Q","period_type":"duration","presentation_role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","parent":"us-gaap:DerivativeLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax","current_period_value":0.6,"prior_period_value":-0.3,"visual_current_value":0.6,"visual_prior_value":-0.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:InterestRateSwapMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:InterestRateSwapMember","member_label":"Interest Rate Swap"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-139","char_anchor":"f-549","text_snippet":"0.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-140","char_anchor":"f-550","text_snippet":"0.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.6,"prior_value":-0.3},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax","date_type":"Q","period_type":"duration","presentation_role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","parent":"us-gaap:DerivativeLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax","current_period_value":0.5,"prior_period_value":-0.2,"visual_current_value":0.5,"visual_prior_value":-0.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-555","text_snippet":"0.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-556","text_snippet":"0.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.5,"prior_value":-0.2},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax","date_type":"Q","period_type":"duration","presentation_role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","parent":"us-gaap:DerivativeLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax","current_period_value":0.6,"prior_period_value":-0.2,"visual_current_value":0.6,"visual_prior_value":-0.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:ForeignExchangeContractMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:ForeignExchangeContractMember","member_label":"Foreign Exchange Contract"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-137","char_anchor":"f-547","text_snippet":"0.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-138","char_anchor":"f-548","text_snippet":"0.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.6,"prior_value":-0.2},{"tag":"us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax","date_type":"Q","period_type":"duration","presentation_role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","presentation_hierarchy":[{"role":"derivativeinstrumentsscheduleofeffectofcashflowhedgesonconsolidatedstatementofearningsdetails","parent":"us-gaap:DerivativeLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax","current_period_value":-0.1,"prior_period_value":null,"visual_current_value":-0.1,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:DerivativeInstrumentRiskAxis=us-gaap:InterestRateSwapMember","dimensions":[{"axis":"us-gaap:DerivativeInstrumentRiskAxis","axis_label":"Derivative Risk","member":"us-gaap:InterestRateSwapMember","member_label":"Interest Rate Swap"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-139","char_anchor":"f-551","text_snippet":"0.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":1,"scale":"millions","current_value":-0.1,"prior_value":null},{"tag":"us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements","date_type":"Q","period_type":"duration","presentation_role":"earningspershareofcommonstockdetails","presentation_hierarchy":[{"role":"earningspershareofcommonstockdetails","parent":"us-gaap:EarningsPerShareAbstract","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,2.0,1],"section_concept":"us-gaap:EarningsPerShareAbstract","calculation_relationships":[{"role":"earningspershareofcommonstockdetails","parent":"us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding","weight":1.0,"order":2.0}],"calculation_role":"earningspershareofcommonstockdetails","calculation_parent":"us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding","calculation_weight":1.0,"calculation_order":2.0,"section_label":"Earnings Per Share"}],"concept_label":"Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements","current_period_value":874679,"prior_period_value":828132.0,"visual_current_value":874679,"visual_prior_value":828132.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-330","text_snippet":"874,679","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-331","text_snippet":"828,132","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":874679,"prior_value":828132.0},{"tag":"us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding","date_type":"Q","period_type":"duration","presentation_role":"earningspershareofcommonstockdetails","presentation_hierarchy":[{"role":"earningspershareofcommonstockdetails","parent":"us-gaap:EarningsPerShareAbstract","order":3.0,"preferred_label_role":"totalLabel","global_sort_position":[0,3.0,2],"section_concept":"us-gaap:EarningsPerShareAbstract","section_label":"Earnings Per Share"}],"concept_label":"Weighted Average Number of Shares Outstanding, Diluted","current_period_value":139167380,"prior_period_value":144407720.0,"visual_current_value":139167380,"visual_prior_value":144407720.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-332","text_snippet":"139,167,380","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-333","text_snippet":"144,407,720","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":139167380,"prior_value":144407720.0},{"tag":"us-gaap:WeightedAverageNumberOfSharesOutstandingBasic","date_type":"Q","period_type":"duration","presentation_role":"earningspershareofcommonstockdetails","presentation_hierarchy":[{"role":"earningspershareofcommonstockdetails","parent":"us-gaap:EarningsPerShareAbstract","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0],"section_concept":"us-gaap:EarningsPerShareAbstract","calculation_relationships":[{"role":"earningspershareofcommonstockdetails","parent":"us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding","weight":1.0,"order":1.0}],"calculation_role":"earningspershareofcommonstockdetails","calculation_parent":"us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding","calculation_weight":1.0,"calculation_order":1.0,"section_label":"Earnings Per Share"}],"concept_label":"Weighted Average Number of Shares Outstanding, Basic","current_period_value":138292701,"prior_period_value":143579588.0,"visual_current_value":138292701,"visual_prior_value":143579588.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-328","text_snippet":"138,292,701","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-329","text_snippet":"143,579,588","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":138292701,"prior_value":143579588.0},{"tag":"us-gaap:FairValueNetAssetLiability","date_type":"Q","period_type":"instant","presentation_role":"fairvaluemeasurementsdetails","presentation_hierarchy":[{"role":"fairvaluemeasurementsdetails","parent":"us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Fair Value, Net Asset (Liability)","current_period_value":18.7,"prior_period_value":27.2,"visual_current_value":18.7,"visual_prior_value":27.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:FairValueByFairValueHierarchyLevelAxis=us-gaap:FairValueInputsLevel1Member","dimensions":[{"axis":"us-gaap:FairValueByFairValueHierarchyLevelAxis","axis_label":"Fair Value Hierarchy","member":"us-gaap:FairValueInputsLevel1Member","member_label":"Fair Value Inputs Level1"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-112","char_anchor":"f-514","text_snippet":"18.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-109","char_anchor":"f-507","text_snippet":"27.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":18.7,"prior_value":27.2},{"tag":"us-gaap:FairValueNetAssetLiability","date_type":"Q","period_type":"instant","presentation_role":"fairvaluemeasurementsdetails","presentation_hierarchy":[{"role":"fairvaluemeasurementsdetails","parent":"us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Fair Value, Net Asset (Liability)","current_period_value":1.6,"prior_period_value":-0.7,"visual_current_value":1.6,"visual_prior_value":-0.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:FairValueByFairValueHierarchyLevelAxis=us-gaap:FairValueInputsLevel2Member","dimensions":[{"axis":"us-gaap:FairValueByFairValueHierarchyLevelAxis","axis_label":"Fair Value Hierarchy","member":"us-gaap:FairValueInputsLevel2Member","member_label":"Fair Value Inputs Level2"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-114","char_anchor":"f-516","text_snippet":"1.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-111","char_anchor":"f-509","text_snippet":"0.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":1.6,"prior_value":-0.7},{"tag":"us-gaap:EffectiveIncomeTaxRateContinuingOperations","date_type":"Q","period_type":"duration","presentation_role":"incometaxesdetails","presentation_hierarchy":[{"role":"incometaxesdetails","parent":"us-gaap:IncomeTaxContingencyLineItems","order":1.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,3.0,2,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Effective Income Tax Rate Reconciliation, Percent","current_period_value":23.7,"prior_period_value":24.6,"visual_current_value":23.7,"visual_prior_value":24.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-564","text_snippet":"23.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-567","text_snippet":"24.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"hundredths","current_value":23.7,"prior_value":24.6},{"tag":"us-gaap:UnrecognizedTaxBenefits","date_type":"Q","period_type":"instant","presentation_role":"incometaxesdetails","presentation_hierarchy":[{"role":"incometaxesdetails","parent":"us-gaap:IncomeTaxContingencyLineItems","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Unrecognized Tax Benefits","current_period_value":13,"prior_period_value":16.2,"visual_current_value":13,"visual_prior_value":16.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-568","text_snippet":"13.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-568","text_snippet":"16.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":13,"prior_value":16.2},{"tag":"us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate","date_type":"Q","period_type":"instant","presentation_role":"incometaxesdetails","presentation_hierarchy":[{"role":"incometaxesdetails","parent":"us-gaap:IncomeTaxContingencyLineItems","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Unrecognized Tax Benefits that Would Impact Effective Tax Rate","current_period_value":4.9,"prior_period_value":4.3,"visual_current_value":4.9,"visual_prior_value":4.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-569","text_snippet":"4.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-569","text_snippet":"4.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":4.9,"prior_value":4.3},{"tag":"us-gaap:InventoryFinishedGoods","date_type":"Q","period_type":"instant","presentation_role":"inventoriesdetails","presentation_hierarchy":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryDisclosureAbstract","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0],"section_concept":null,"calculation_relationships":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryGross","weight":1.0,"order":1.0}],"calculation_role":"inventoriesdetails","calculation_parent":"us-gaap:InventoryGross","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Inventory, Finished Goods, Gross","current_period_value":182.6,"prior_period_value":189.8,"visual_current_value":182.6,"visual_prior_value":189.8,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-292","text_snippet":"182.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-287","text_snippet":"189.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":182.6,"prior_value":189.8},{"tag":"us-gaap:InventoryGross","date_type":"Q","period_type":"instant","presentation_role":"inventoriesdetails","presentation_hierarchy":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryDisclosureAbstract","order":4.0,"preferred_label_role":"totalLabel","global_sort_position":[0,4.0,3],"section_concept":null,"calculation_relationships":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryNet","weight":1.0,"order":1.0}],"calculation_role":"inventoriesdetails","calculation_parent":"us-gaap:InventoryNet","calculation_weight":1.0,"calculation_order":1.0,"section_label":null}],"concept_label":"Inventory, Gross","current_period_value":537.2,"prior_period_value":576.2,"visual_current_value":537.2,"visual_prior_value":576.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-298","text_snippet":"537.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-293","text_snippet":"576.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":537.2,"prior_value":576.2},{"tag":"us-gaap:InventoryLIFOReserve","date_type":"Q","period_type":"instant","presentation_role":"inventoriesdetails","presentation_hierarchy":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryDisclosureAbstract","order":5.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,5.0,4],"section_concept":null,"calculation_relationships":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryNet","weight":-1.0,"order":2.0}],"calculation_role":"inventoriesdetails","calculation_parent":"us-gaap:InventoryNet","calculation_weight":-1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Inventory, LIFO Reserve","current_period_value":48.7,"prior_period_value":43.6,"visual_current_value":-48.7,"visual_prior_value":-43.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-300","text_snippet":"48.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-295","text_snippet":"43.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-48.7,"prior_value":-43.6},{"tag":"us-gaap:InventoryRawMaterials","date_type":"Q","period_type":"instant","presentation_role":"inventoriesdetails","presentation_hierarchy":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryDisclosureAbstract","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,3.0,2],"section_concept":null,"calculation_relationships":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryGross","weight":1.0,"order":3.0}],"calculation_role":"inventoriesdetails","calculation_parent":"us-gaap:InventoryGross","calculation_weight":1.0,"calculation_order":3.0,"section_label":null}],"concept_label":"Inventory, Raw Materials, Gross","current_period_value":311,"prior_period_value":342.7,"visual_current_value":311,"visual_prior_value":342.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-296","text_snippet":"311.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-291","text_snippet":"342.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":311,"prior_value":342.7},{"tag":"us-gaap:InventoryWorkInProcess","date_type":"Q","period_type":"instant","presentation_role":"inventoriesdetails","presentation_hierarchy":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryDisclosureAbstract","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,2.0,1],"section_concept":null,"calculation_relationships":[{"role":"inventoriesdetails","parent":"us-gaap:InventoryGross","weight":1.0,"order":2.0}],"calculation_role":"inventoriesdetails","calculation_parent":"us-gaap:InventoryGross","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Inventory, Work in Process, Gross","current_period_value":43.6,"prior_period_value":43.7,"visual_current_value":43.6,"visual_prior_value":43.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-294","text_snippet":"43.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-289","text_snippet":"43.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":43.6,"prior_value":43.7},{"tag":"us-gaap:ProductWarrantyAccrual","date_type":"Q","period_type":"instant","presentation_role":"productwarrantiesdetails","presentation_hierarchy":[{"role":"productwarrantiesdetails","parent":"us-gaap:MovementInStandardAndExtendedProductWarrantyIncreaseDecreaseRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Standard and Extended Product Warranty Accrual","current_period_value":210.4,"prior_period_value":194.3,"visual_current_value":210.4,"visual_prior_value":194.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-314","text_snippet":"210.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-12","char_anchor":"f-315","text_snippet":"194.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":210.4,"prior_value":194.3},{"tag":"us-gaap:ProductWarrantyAccrualAdditionsFromBusinessAcquisition","date_type":"Q","period_type":"duration","presentation_role":"productwarrantiesdetails","presentation_hierarchy":[{"role":"productwarrantiesdetails","parent":"us-gaap:MovementInStandardAndExtendedProductWarrantyIncreaseDecreaseRollForward","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Standard and Extended Product Warranty Accrual, Increase from Business Combination","current_period_value":0.5,"prior_period_value":1.1,"visual_current_value":0.5,"visual_prior_value":1.1,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-310","text_snippet":"0.5","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-311","text_snippet":"1.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":0.5,"prior_value":1.1},{"tag":"us-gaap:ProductWarrantyAccrualPayments","date_type":"Q","period_type":"duration","presentation_role":"productwarrantiesdetails","presentation_hierarchy":[{"role":"productwarrantiesdetails","parent":"us-gaap:MovementInStandardAndExtendedProductWarrantyIncreaseDecreaseRollForward","order":4.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Standard and Extended Product Warranty Accrual, Decrease for Payments","current_period_value":20.9,"prior_period_value":16.6,"visual_current_value":-20.9,"visual_prior_value":-16.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-312","text_snippet":"20.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-313","text_snippet":"16.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-20.9,"prior_value":-16.6},{"tag":"us-gaap:ProductWarrantyAccrualWarrantiesIssued","date_type":"Q","period_type":"duration","presentation_role":"productwarrantiesdetails","presentation_hierarchy":[{"role":"productwarrantiesdetails","parent":"us-gaap:MovementInStandardAndExtendedProductWarrantyIncreaseDecreaseRollForward","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Standard and Extended Product Warranty Accrual, Increase for Warranties Issued","current_period_value":21.1,"prior_period_value":19.4,"visual_current_value":21.1,"visual_prior_value":19.4,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-308","text_snippet":"21.1","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-309","text_snippet":"19.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":21.1,"prior_value":19.4},{"tag":"aos:NumberOfWholesaleDistributors","date_type":"Q","period_type":"duration","presentation_role":"revenuerecognitionnarrativedetails","presentation_hierarchy":[{"role":"revenuerecognitionnarrativedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":5.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,5.0,4],"section_concept":null,"section_label":null}],"concept_label":"Number of wholesale distributors (more than)","current_period_value":800,"prior_period_value":null,"visual_current_value":800,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:ProductOrServiceAxis=aos:WaterHeatersMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ProductOrServiceAxis","axis_label":"Product Lines","member":"aos:WaterHeatersMember","member_label":"Water Heaters [Member]"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-47","char_anchor":"f-245","text_snippet":"800","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":800,"prior_value":null},{"tag":"aos:RevenueFromContractWithCustomerPaymentTerms","date_type":"Q","period_type":"duration","presentation_role":"revenuerecognitionnarrativedetails","presentation_hierarchy":[{"role":"revenuerecognitionnarrativedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Payment terms","current_period_value":30,"prior_period_value":null,"visual_current_value":30,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:RangeAxis=srt:MinimumMember","dimensions":[{"axis":"srt:RangeAxis","axis_label":"Range","member":"srt:MinimumMember","member_label":"Minimum"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-45","char_anchor":"f-238","text_snippet":"30","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":null,"current_value":30,"prior_value":null},{"tag":"aos:RevenueFromContractWithCustomerPaymentTerms","date_type":"Q","period_type":"duration","presentation_role":"revenuerecognitionnarrativedetails","presentation_hierarchy":[{"role":"revenuerecognitionnarrativedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Payment terms","current_period_value":90,"prior_period_value":null,"visual_current_value":90,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:RangeAxis=srt:MaximumMember","dimensions":[{"axis":"srt:RangeAxis","axis_label":"Range","member":"srt:MaximumMember","member_label":"Maximum"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-46","char_anchor":"f-239","text_snippet":"90","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":null,"current_value":90,"prior_value":null},{"tag":"us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent","date_type":"Q","period_type":"instant","presentation_role":"revenuerecognitionnarrativedetails","presentation_hierarchy":[{"role":"revenuerecognitionnarrativedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":3.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,4.0,3,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Accounts Receivable, Allowance for Credit Loss, Current","current_period_value":15.3,"prior_period_value":14.6,"visual_current_value":15.3,"visual_prior_value":14.6,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-242","text_snippet":"15.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-240","text_snippet":"14.6","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":15.3,"prior_value":14.6},{"tag":"us-gaap:ContractWithCustomerLiabilityCurrent","date_type":"Q","period_type":"instant","presentation_role":"revenuerecognitionnarrativedetails","presentation_hierarchy":[{"role":"revenuerecognitionnarrativedetails","parent":"us-gaap:DisaggregationOfRevenueLineItems","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,4.0,3,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Contract with Customer, Liability, Current","current_period_value":28.9,"prior_period_value":43.0,"visual_current_value":28.9,"visual_prior_value":43.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-5","char_anchor":"f-240","text_snippet":"28.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-5","char_anchor":"f-238","text_snippet":"43.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":28.9,"prior_value":43.0},{"tag":"us-gaap:OperatingIncomeLoss","date_type":"Q","period_type":"duration","presentation_role":"segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Operating Income (Loss)","current_period_value":161.8,"prior_period_value":184.0,"visual_current_value":161.8,"visual_prior_value":184.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"__NONE__","dimensions":null,"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-1","char_anchor":"f-427","text_snippet":"161.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-4","char_anchor":"f-479","text_snippet":"184.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":161.8,"prior_value":184.0},{"tag":"us-gaap:OperatingIncomeLoss","date_type":"Q","period_type":"duration","presentation_role":"segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Operating Income (Loss)","current_period_value":-26,"prior_period_value":-20.9,"visual_current_value":-26,"visual_prior_value":-20.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:CorporateNonSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:CorporateNonSegmentMember","member_label":"Corporate Non Segment"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-93","char_anchor":"f-426","text_snippet":"26.0","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-100","char_anchor":"f-478","text_snippet":"20.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":-26,"prior_value":-20.9},{"tag":"us-gaap:OperatingIncomeLoss","date_type":"Q","period_type":"duration","presentation_role":"segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Operating Income (Loss)","current_period_value":187.8,"prior_period_value":204.9,"visual_current_value":187.8,"visual_prior_value":204.9,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-96","char_anchor":"f-425","text_snippet":"187.8","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-103","char_anchor":"f-477","text_snippet":"204.9","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":187.8,"prior_value":204.9},{"tag":"us-gaap:OperatingIncomeLoss","date_type":"Q","period_type":"duration","presentation_role":"segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Operating Income (Loss)","current_period_value":175.4,"prior_period_value":185.2,"visual_current_value":175.4,"visual_prior_value":185.2,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:NorthAmericaSegmentMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:NorthAmericaSegmentMember","member_label":"North America"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-54","char_anchor":"f-423","text_snippet":"175.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-55","char_anchor":"f-475","text_snippet":"185.2","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":175.4,"prior_value":185.2},{"tag":"us-gaap:OperatingIncomeLoss","date_type":"Q","period_type":"duration","presentation_role":"segmentresultsscheduleofreportablesegmentdetails","presentation_hierarchy":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:SegmentReportingInformationLineItems","order":6.0,"preferred_label_role":"totalLabel","global_sort_position":[0,1.0,0,3.0,2,6.0,5],"section_concept":null,"calculation_relationships":[{"role":"segmentresultsscheduleofreportablesegmentdetails","parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","weight":1.0,"order":2.0}],"calculation_role":"segmentresultsscheduleofreportablesegmentdetails","calculation_parent":"us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest","calculation_weight":1.0,"calculation_order":2.0,"section_label":null}],"concept_label":"Operating Income (Loss)","current_period_value":12.4,"prior_period_value":19.7,"visual_current_value":12.4,"visual_prior_value":19.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"srt:ConsolidationItemsAxis=us-gaap:OperatingSegmentsMember|us-gaap:StatementBusinessSegmentsAxis=aos:RestOfWorldMember","dimensions":[{"axis":"srt:ConsolidationItemsAxis","axis_label":"Consolidation Items","member":"us-gaap:OperatingSegmentsMember","member_label":"Operating Segments"},{"axis":"us-gaap:StatementBusinessSegmentsAxis","axis_label":"Business Segments","member":"aos:RestOfWorldMember","member_label":"Rest of World"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-60","char_anchor":"f-424","text_snippet":"12.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-61","char_anchor":"f-476","text_snippet":"19.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":12.4,"prior_value":19.7},{"tag":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodFairValue","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationnarrativedetails","presentation_hierarchy":[{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Value of units share units granted","current_period_value":2.4,"prior_period_value":2.3,"visual_current_value":2.4,"visual_prior_value":2.3,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-358","text_snippet":"2.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-87","char_anchor":"f-359","text_snippet":"2.3","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":1,"scale":"millions","current_value":2.4,"prior_value":2.3},{"tag":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodFairValue","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationnarrativedetails","presentation_hierarchy":[{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Value of units share units granted","current_period_value":14.4,"prior_period_value":13.7,"visual_current_value":14.4,"visual_prior_value":13.7,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-80","char_anchor":"f-339","text_snippet":"14.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-81","char_anchor":"f-340","text_snippet":"13.7","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"millions","current_value":14.4,"prior_value":13.7},{"tag":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardPotentialPayoutPercentOfTargetAwards","date_type":"Q","period_type":"instant","presentation_role":"sharebasedcompensationnarrativedetails","presentation_hierarchy":[{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":6.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,6.0,5],"section_concept":null,"section_label":null}],"concept_label":"Potential payouts range","current_period_value":150,"prior_period_value":null,"visual_current_value":150,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"srt:RangeAxis=srt:MaximumMember|us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"srt:RangeAxis","axis_label":"Range","member":"srt:MaximumMember","member_label":"Maximum"},{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-86","char_anchor":"f-355","text_snippet":"150","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"hundredths","current_value":150,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant","date_type":"Q","period_type":"instant","presentation_role":"sharebasedcompensationnarrativedetails","presentation_hierarchy":[{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":1.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant","current_period_value":1893236,"prior_period_value":null,"visual_current_value":1893236,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:PlanNameAxis=aos:AOSmithCombinedCompensationPlanMember","dimensions":[{"axis":"us-gaap:PlanNameAxis","axis_label":"Plan Name","member":"aos:AOSmithCombinedCompensationPlanMember","member_label":"A.O. Smith Combined Compensation Plan"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-79","char_anchor":"f-335","text_snippet":"1,893,236","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":1893236,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationnarrativedetails|sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,3.0,2],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,2.0,1],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period","current_period_value":30015,"prior_period_value":35365.0,"visual_current_value":30015,"visual_prior_value":35365.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-356","text_snippet":"30,015","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-87","char_anchor":"f-357","text_snippet":"35,365","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":30015,"prior_value":35365.0},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationnarrativedetails|sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationnarrativedetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,4.0,3,3.0,2],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,2.0,1],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":2.0,"preferred_label_role":"verboseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period","current_period_value":182070,"prior_period_value":209366.0,"visual_current_value":182070,"visual_prior_value":209366.0,"end_current":"2026-03-31","end_prior":"2025-03-31","axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-80","char_anchor":"f-337","text_snippet":"182,070","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":{"context_ref":"c-81","char_anchor":"f-338","text_snippet":"209,366","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114225000075/aos-20250331.htm","accession":"0000091142-25-000075"}},"collision_flag":0,"scale":"units","current_value":182070,"prior_value":209366.0},{"tag":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustments","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Performance adjustments (in shares)","current_period_value":10911,"prior_period_value":null,"visual_current_value":10911,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-370","text_snippet":"10,911","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":10911,"prior_value":null},{"tag":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentsWeightedAverageGrantDateFairValue","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":4.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,4.0,3],"section_concept":null,"section_label":null}],"concept_label":"Performance adjustments (in USD per share)","current_period_value":65.68,"prior_period_value":null,"visual_current_value":65.68,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-371","text_snippet":"65.68","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":65.68,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,2.0,1],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value","current_period_value":79.03,"prior_period_value":null,"visual_current_value":79.03,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-80","char_anchor":"f-348","text_snippet":"79.03","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":79.03,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,2.0,1],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":2.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,2.0,1],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value","current_period_value":79.09,"prior_period_value":null,"visual_current_value":79.09,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-367","text_snippet":"79.09","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":79.09,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber","date_type":"Q","period_type":"instant","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number","current_period_value":660082,"prior_period_value":null,"visual_current_value":660082,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-83","char_anchor":"f-351","text_snippet":"660,082","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":660082,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber","date_type":"Q","period_type":"instant","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number","current_period_value":117521,"prior_period_value":null,"visual_current_value":117521,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-89","char_anchor":"f-372","text_snippet":"117,521","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":117521,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue","date_type":"Q","period_type":"instant","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value","current_period_value":72.09,"prior_period_value":null,"visual_current_value":72.09,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-83","char_anchor":"f-352","text_snippet":"72.09","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":72.09,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue","date_type":"Q","period_type":"instant","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":1.0,"preferred_label_role":"periodStartLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,1.0,0],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value","current_period_value":74.71,"prior_period_value":null,"visual_current_value":74.71,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-89","char_anchor":"f-373","text_snippet":"74.71","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":74.71,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":3.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,3.0,2],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":3.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period","current_period_value":153295,"prior_period_value":null,"visual_current_value":-153295,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-80","char_anchor":"f-349","text_snippet":"153,295","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":-153295,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":3.0,"preferred_label_role":"negatedLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,3.0,2],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward","order":3.0,"preferred_label_role":"negatedTerseLabel","global_sort_position":[0,1.0,0,2.0,1,1.0,0,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period","current_period_value":33107,"prior_period_value":null,"visual_current_value":-33107,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-368","text_snippet":"33,107","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":-33107,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,3.0,2],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value","current_period_value":67.14,"prior_period_value":null,"visual_current_value":67.14,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:RestrictedStockUnitsRSUMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:RestrictedStockUnitsRSUMember","member_label":"Restricted Stock Units RSU"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-80","char_anchor":"f-350","text_snippet":"67.14","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":67.14,"prior_value":null},{"tag":"us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue","date_type":"Q","period_type":"duration","presentation_role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails|sharebasedcompensationscheduleofshareunitactivityunderplandetails","presentation_hierarchy":[{"role":"sharebasedcompensationscheduleofshareunitactivityunderplandetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,3.0,2],"section_concept":null,"section_label":null},{"role":"sharebasedcompensationscheduleofperformancestockunitactivitydetails","parent":"aos:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward","order":3.0,"preferred_label_role":"terseLabel","global_sort_position":[0,1.0,0,2.0,1,2.0,1,3.0,2],"section_concept":null,"section_label":null}],"concept_label":"Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value","current_period_value":67.14,"prior_period_value":null,"visual_current_value":67.14,"visual_prior_value":null,"end_current":"2026-03-31","end_prior":null,"axis_key":"us-gaap:AwardTypeAxis=us-gaap:PerformanceSharesMember","dimensions":[{"axis":"us-gaap:AwardTypeAxis","axis_label":"Award Type","member":"us-gaap:PerformanceSharesMember","member_label":"Performance Shares"}],"source":"xbrl","source_ref":{"type":"xbrl_context","current":{"context_ref":"c-84","char_anchor":"f-369","text_snippet":"67.14","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"prior":null},"collision_flag":0,"scale":"units","current_value":67.14,"prior_value":null}],"producer_parser_version":"941f25a6","producer_source":"prewarm_manifest","_financials_schema_version":1,"cache_version":13,"semantic_status":"partial","coverage_status":"partial","scope_warnings":[{"type":"mixed_scope_cash_flow","scope_status":"mixed_scope_warning","statement_role":"cash_flow","affected_tags":["us-gaap:NetCashProvidedByUsedInOperatingActivities"],"message":"Operating cash flow is reported as consolidated cash flow while the filing also discloses discontinued operations or wind-down activity (Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation). Do not divide this consolidated CFO by continuing-operations revenue without an adjustment.","evidence":{"cash_flow_fact_source_ref":{"context_ref":"c-1","char_anchor":"f-151","text_snippet":"129.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"disclosure_signal":{"tag":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","concept_label":"Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation","axis_key":"__NONE__","dimensions":null}}}],"scope_bridges":[{"id":"cash_flow_scope_bridge:operating_cash_flow:2026-Q1:direct_discontinued","type":"cash_flow_scope_bridge","scope_status":"mixed_scope_bridge_candidate","statement_role":"cash_flow","base_concept":"operating_cash_flow","reported_scope":"consolidated","target_scope":"continuing_operations","reported_value":129.4,"reported_scale":"millions","adjusted_value":0.0,"adjusted_scale":"millions","confidence":"high","adjustments":[{"label":"Reported discontinued-operations operating cash flow","operation":"remove_discontinued_operating_cash_flow","amount":129.4,"scale":"millions","source_tag":"us-gaap:NetCashProvidedByUsedInOperatingActivities","statement_role":"cash_flow","reason":"The filing reports discontinued-operations cash flow directly.","source_ref":{"context_ref":"c-1","char_anchor":"f-151","text_snippet":"129.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"}}],"evidence":{"reported_fact_source_ref":{"context_ref":"c-1","char_anchor":"f-151","text_snippet":"129.4","filing_url":"https://www.sec.gov/Archives/edgar/data/91142/000009114226000084/aos-20260331.htm","accession":"0000091142-26-000084"},"disclosure_signal":{"tag":"us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect","concept_label":"Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation","axis_key":"__NONE__","dimensions":null}},"message":"Operating cash flow is consolidated while the filing discloses discontinued operations or wind-down activity. Use this bridge as an evidence-backed same-scope CFO candidate; do not overwrite the reported CFO fact.","ticker":"AOS","period":"2026-Q1"}]}