$AOS
A O Smith Corp Stock $aos

$aos Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000009114221000025 Filed on February 12, 2021

Income Statement

Concept	2020 Q4	2020 Q3	2020 Q2
Revenue	$834.5M	$760.0M	$663.9M
YoY Change	11.13%	4.37%	-13.26%
Cost Of Revenue	$510.4M	$462.9M	$416.4M
YoY Change	11.95%	4.26%	-8.82%
Gross Profit	$324.1M	$297.1M	$247.5M
YoY Change	9.86%	4.54%	-19.83%
Gross Profit Margin	38.84%	39.09%	37.28%
Selling, General & Admin	$171.2M	$159.4M	$155.9M
YoY Change	-4.84%	-7.49%	-12.76%
% of Gross Profit	52.82%	53.65%	62.99%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$19.30M	$20.70M	$19.90M
YoY Change	-4.46%	5.08%	9.34%
% of Gross Profit	5.95%	6.97%	8.04%
Operating Expenses	$171.2M	$159.4M	$155.9M
YoY Change	-3.28%	-7.49%	-9.94%
Operating Profit	$152.9M	$149.8M	$99.30M
YoY Change	29.58%	19.17%	-26.77%
Interest Expense	-$1.000M	$1.600M	$2.500M
YoY Change	-60.0%	-48.39%	-173.53%
% of Operating Profit	-0.65%	1.07%	2.52%
Other Income/Expense, Net		$2.800M	$4.000M
YoY Change		-30.0%
Pretax Income	$151.9M	$137.3M	$87.00M
YoY Change	31.52%	21.72%	-34.19%
Income Tax	$31.90M	$31.90M	$19.20M
% Of Pretax Income	21.0%	23.23%	22.07%
Net Earnings	$120.0M	$105.4M	$67.80M
YoY Change	31.43%	20.73%	-33.59%
Net Earnings / Revenue	14.38%	13.87%	10.21%
Basic Earnings Per Share	$0.74	$0.65	$0.42
Diluted Earnings Per Share	$0.74	$0.65	$0.42
COMMON SHARES
Basic Shares Outstanding		161.4M shares	161.2M shares
Diluted Shares Outstanding		162.5M shares	162.2M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2020 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$689.6M	$509.0M	$568.7M
YoY Change	25.06%	-0.93%	-1.57%
Cash & Equivalents	$573.1M	$377.9M	$442.7M
Short-Term Investments	$116.5M	$131.1M	$126.0M
Other Short-Term Assets	$43.30M	$45.80M	$53.80M
YoY Change	-23.36%	-31.13%	-11.66%
Inventory	$300.1M	$302.6M	$306.0M
Prepaid Expenses
Receivables	$585.0M	$572.9M	$515.9M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$1.618B	$1.430B	$1.444B
YoY Change	7.84%	-4.93%	-9.53%
LONG-TERM ASSETS
Property, Plant & Equipment	$541.3M	$537.1M	$579.0M
YoY Change	-0.75%	-9.26%	-3.87%
Goodwill	$546.8M	$544.8M
YoY Change	0.15%
Intangibles	$323.9M	$325.8M
YoY Change	-4.28%
Long-Term Investments
YoY Change
Other Assets	$89.10M	$90.90M	$87.30M
YoY Change	10.14%	7.32%	2.59%
Total Long-Term Assets	$1.543B	$1.541B	$1.540B
YoY Change	-0.96%	-1.45%	-2.48%
TOTAL ASSETS
Total Short-Term Assets	$1.618B	$1.430B	$1.444B
Total Long-Term Assets	$1.543B	$1.541B	$1.540B
Total Assets	$3.161B	$2.971B	$2.984B
YoY Change	3.36%	-3.16%	-6.03%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$595.2M	$516.9M	$435.7M
YoY Change	16.8%	7.0%	-10.79%
Accrued Expenses	$161.9M	$166.1M	$248.1M
YoY Change	12.67%	-15.17%	29.42%
Deferred Revenue	$90.00M	$68.70M
YoY Change	81.45%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$6.800M	$6.800M	$6.800M
YoY Change	0.0%	0.0%	0.0%
Total Short-Term Liabilities	$886.3M	$805.9M	$735.4M
YoY Change	15.63%	10.34%	0.66%
LONG-TERM LIABILITIES
Long-Term Debt	$106.4M	$107.1M	$274.3M
YoY Change	-61.62%	-65.72%	-22.03%
Other Long-Term Liabilities	$177.2M	$266.0M	$316.4M
YoY Change	-6.04%	-27.89%	-14.05%
Total Long-Term Liabilities	$283.6M	$373.1M	$590.7M
YoY Change	-39.12%	-45.24%	-17.95%
TOTAL LIABILITIES
Total Short-Term Liabilities	$886.3M	$805.9M	$735.4M
Total Long-Term Liabilities	$283.6M	$373.1M	$590.7M
Total Liabilities	$1.312B	$1.224B	$1.326B
YoY Change	-5.66%	-13.3%	-8.58%
SHAREHOLDERS EQUITY
Retained Earnings	$2.510B	$2.432B
YoY Change	8.01%
Common Stock	$520.4M	$518.7M
YoY Change	2.24%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$1.156B	$1.162B
YoY Change	3.88%
Treasury Stock Shares
Shareholders Equity	$1.848B	$1.747B	$1.658B
YoY Change
Total Liabilities & Shareholders Equity	$3.161B	$2.971B	$2.984B
YoY Change	3.36%	-3.16%	-6.03%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2020 Q2
OPERATING ACTIVITIES
Net Income	$120.0M	$105.4M	$67.80M
YoY Change	31.43%	20.73%	-33.59%
Depreciation, Depletion And Amortization	$19.30M	$20.70M	$19.90M
YoY Change	-4.46%	5.08%	9.34%
Cash From Operating Activities	$231.7M	$151.1M	$125.2M
YoY Change	31.5%	10.86%	2.54%
INVESTING ACTIVITIES
Capital Expenditures	-$20.10M	-$11.90M	-$12.00M
YoY Change	42.55%	-13.77%	-23.08%
Acquisitions
YoY Change
Other Investing Activities	$19.50M	$100.0K	$9.800M
YoY Change	-84.25%	-101.0%	-108.58%
Cash From Investing Activities	-$600.0K	-$11.80M	-$2.200M
YoY Change	-100.55%	-50.42%	-98.31%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-35.90M	-204.1M	-96.40M
YoY Change	-72.66%	16.83%	98.76%
NET CHANGE
Cash From Operating Activities	231.7M	151.1M	125.2M
Cash From Investing Activities	-600.0K	-11.80M	-2.200M
Cash From Financing Activities	-35.90M	-204.1M	-96.40M
Net Change In Cash	195.2M	-64.80M	26.60M
YoY Change	26.26%	4.18%	-147.33%
FREE CASH FLOW
Cash From Operating Activities	$231.7M	$151.1M	$125.2M
Capital Expenditures	-$20.10M	-$11.90M	-$12.00M
Free Cash Flow	$251.8M	$163.0M	$137.2M
YoY Change	32.32%	8.59%	-0.36%

Facts In Submission

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CY2020	dei	Trading Symbol TradingSymbol	AOS
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CY2020	dei	Entity File Number EntityFileNumber	1-475
CY2020	dei	Entity Registrant Name EntityRegistrantName	A. O. Smith Corporation
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	11270 West Park Place
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CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	WI
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CY2018	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	40000000.0	USD
CY2020	us-gaap	Increase Decrease In Other Noncurrent Assets And Liabilities Net IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet	5900000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Assets And Liabilities Net IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet	38000000.0	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	448900000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	107000000.0	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2020	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	157400000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	272700000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	523400000	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	226000000.0	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	478000000.0	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	595900000	USD
CY2020	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	56800000	USD
CY2019	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	64400000	USD
CY2018	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	85200000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	11800000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	33900000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-12700000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	170800000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	62600000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	189000000.0	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	56700000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	287700000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	202600000	USD
CY2020	aos	Payments For Proceeds From Stock Options Activity PaymentsForProceedsFromStockOptionsActivity	11400000	USD
CY2019	aos	Payments For Proceeds From Stock Options Activity PaymentsForProceedsFromStockOptionsActivity	-500000	USD
CY2018	aos	Payments For Proceeds From Stock Options Activity PaymentsForProceedsFromStockOptionsActivity	900000	USD
CY2020	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	0	USD
CY2019	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	1000000.0	USD
CY2018	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	2300000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	158700000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	149200000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	130100000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-374800000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-375800000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-523100000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	199100000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	114300000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-86900000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	374000000.0	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	259700000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	346600000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	573100000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	374000000.0	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	259700000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	1848300000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1666800000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1717000000.0	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Use of estimates. </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with accounting principles generally accepted in the United States (U.S.) requires management to make estimates and assumptions that affect the amounts reported in the accompanying financial statements and notes. Actual results could differ from those estimates.</span>
CY2020Q4	us-gaap	Notes Payable Fair Value Disclosure NotesPayableFairValueDisclosure	123300000	USD
CY2020Q4	us-gaap	Notes Payable NotesPayable	113200000	USD
CY2019Q4	us-gaap	Notes Payable Fair Value Disclosure NotesPayableFairValueDisclosure	122100000	USD
CY2019Q4	us-gaap	Notes Payable NotesPayable	120000000.0	USD
CY2020Q4	us-gaap	Percentage Of Lifo Inventory PercentageOfLIFOInventory	0.67
CY2019Q4	us-gaap	Percentage Of Lifo Inventory PercentageOfLIFOInventory	0.65
CY2019Q4	us-gaap	Product Warranty Accrual ProductWarrantyAccrual	134300000	USD
CY2018Q4	us-gaap	Product Warranty Accrual ProductWarrantyAccrual	139400000	USD
CY2020	us-gaap	Extended Product Warranty Accrual Warranties Issued ExtendedProductWarrantyAccrualWarrantiesIssued	56100000	USD
CY2019	us-gaap	Extended Product Warranty Accrual Warranties Issued ExtendedProductWarrantyAccrualWarrantiesIssued	44300000	USD
CY2020	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	48100000	USD
CY2019	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	49400000	USD
CY2020Q4	us-gaap	Product Warranty Accrual ProductWarrantyAccrual	142300000	USD
CY2019Q4	us-gaap	Product Warranty Accrual ProductWarrantyAccrual	134300000	USD
CY2020	us-gaap	Advertising Expense AdvertisingExpense	97000000.0	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	110700000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	132100000	USD
CY2020	aos	Amortization Of Advertising Costs AmortizationOfAdvertisingCosts	27000000.0	USD
CY2019	aos	Amortization Of Advertising Costs AmortizationOfAdvertisingCosts	28500000	USD
CY2018	aos	Amortization Of Advertising Costs AmortizationOfAdvertisingCosts	38700000	USD
CY2020	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	80700000	USD
CY2019	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	87900000	USD
CY2018	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	94000000.0	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4200000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	2300000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	2400000	USD
CY2020	aos	Minimum Percentage Of Amount Likely To Be Realized Upon Ultimate Settlement To Recognize Tax Benefits MinimumPercentageOfAmountLikelyToBeRealizedUponUltimateSettlementToRecognizeTaxBenefits	0.50
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	161530589	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	165450441	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	170589345	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1073560	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1260456	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1604695	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	162604149	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	166710897	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172194040	shares
CY2020Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	90000000.0	USD
CY2019Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	49600000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	5600000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	6700000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2895300000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2992700000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3187900000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	50700000	USD
CY2020	aos	Lessee Operating Lease Termination Period LesseeOperatingLeaseTerminationPeriod	P1Y
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	11100000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	12000000.0	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	34400000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	38700000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	45500000	USD
CY2020Q4	aos	Rent Incentives And Deferrals RentIncentivesAndDeferrals	3900000	USD
CY2019Q4	aos	Rent Incentives And Deferrals RentIncentivesAndDeferrals	3800000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	41600000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	46900000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0349
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1800000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	1600000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2000000.0	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	2100000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	24000000.0	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	12400000	USD
CY2019Q4	us-gaap	Inventory Raw Materials InventoryRawMaterials	168300000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	10200000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	5600000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4600000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	2900000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	21000000.0	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	56700000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	11200000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	45500000	USD
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	7700000	USD
CY2020	us-gaap	Severance Costs1 SeveranceCosts1	6800000	USD
CY2020	us-gaap	Other Restructuring Costs OtherRestructuringCosts	900000	USD
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	7700000	USD
CY2018Q1	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	6700000	USD
CY2018Q1	us-gaap	Severance Costs1 SeveranceCosts1	4000000.0	USD
CY2018Q1	us-gaap	Business Exit Costs1 BusinessExitCosts1	2100000	USD
CY2018Q1	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	600000	USD
CY2019	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	14200000	USD
CY2018	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	-3500000	USD
CY2017Q4	us-gaap	Restructuring Reserve RestructuringReserve	0	USD
CY2018	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	6700000	USD
CY2018	us-gaap	Payments For Restructuring PaymentsForRestructuring	5200000	USD
CY2018Q4	us-gaap	Restructuring Reserve RestructuringReserve	1500000	USD
CY2019	us-gaap	Payments For Restructuring PaymentsForRestructuring	1000000.0	USD
CY2019Q4	us-gaap	Restructuring Reserve RestructuringReserve	500000	USD
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	7700000	USD
CY2020	us-gaap	Payments For Restructuring PaymentsForRestructuring	6500000	USD
CY2020Q4	us-gaap	Restructuring Reserve RestructuringReserve	1700000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-4500000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-62400000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	54600000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-2900000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-6300000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	7700000	USD
CY2020	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	-4700000	USD
CY2019	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	4800000	USD
CY2018	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	-10000000.0	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	85600000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-35400000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	8800000	USD
CY2020	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	29300000	USD
CY2019Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	465500000	USD
CY2020	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	-130400000	USD
CY2019	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	-32600000	USD
CY2018	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	40000000.0	USD
CY2020	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	3400000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	-10100000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	7000000.0	USD
CY2020Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	143400000	USD
CY2019Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	136800000	USD
CY2020Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	21800000	USD
CY2019Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	21700000	USD
CY2020Q4	us-gaap	Inventory Raw Materials InventoryRawMaterials	159200000	USD
CY2020Q4	us-gaap	Inventory Gross InventoryGross	324400000	USD
CY2019Q4	us-gaap	Inventory Gross InventoryGross	326800000	USD
CY2020Q4	us-gaap	Inventory Lifo Reserve InventoryLIFOReserve	24300000	USD
CY2019Q4	us-gaap	Inventory Lifo Reserve InventoryLIFOReserve	23800000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	300100000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	303000000.0	USD
CY2020	us-gaap	Effect Of Lifo Inventory Liquidation On Income EffectOfLIFOInventoryLiquidationOnIncome	200000	USD
CY2019	us-gaap	Effect Of Lifo Inventory Liquidation On Income EffectOfLIFOInventoryLiquidationOnIncome	700000	USD
CY2018	us-gaap	Effect Of Lifo Inventory Liquidation On Income EffectOfLIFOInventoryLiquidationOnIncome	400000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1222600000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1156900000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	681300000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	611500000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	541300000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	545400000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	513000000.0	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	31000000.0	USD
CY2019	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	2000000.0	USD
CY2019Q4	us-gaap	Goodwill Goodwill	546000000.0	USD
CY2020	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	800000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	546800000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	281700000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	141800000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	139900000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	281700000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	127100000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	154600000	USD
CY2020Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	465700000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	141800000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	323900000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	127100000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	338400000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	14500000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	15800000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	14300000	USD
CY2020	us-gaap	Acquired Finite Lived Intangible Assets Weighted Average Useful Life AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife	P13Y
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Impairment Of Intangible Assets Excluding Goodwill ImpairmentOfIntangibleAssetsExcludingGoodwill	0	USD
CY2018	us-gaap	Impairment Of Intangible Assets Excluding Goodwill ImpairmentOfIntangibleAssetsExcludingGoodwill	0	USD
CY2019	us-gaap	Impairment Of Intangible Assets Excluding Goodwill ImpairmentOfIntangibleAssetsExcludingGoodwill	0	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	113200000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	284000000.0	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	6800000	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	6800000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	106400000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	277200000	USD
CY2016Q4	us-gaap	Line Of Credit Facility Current Borrowing Capacity LineOfCreditFacilityCurrentBorrowingCapacity	500000000	USD
CY2016	aos	Number Of Banks Involved In Multi Year Multi Currency Revolving Credit Agreement NumberOfBanksInvolvedInMultiYearMultiCurrencyRevolvingCreditAgreement	9	bank
CY2016Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	700000000	USD
CY2020Q4	aos	Long Term Debt Fixed Interest Payment LongTermDebtFixedInterestPayment	22200000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	6800000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	6800000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	10000000.0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	10000000.0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	10000000.0	USD
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	3000000	shares
CY2020Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1
CY2020	aos	Common Stock Conversion Basis Ratio CommonStockConversionBasisRatio	1
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.98
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.90
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.76
CY2019Q2	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	3000000	shares
CY2020	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1348391	shares
CY2020	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	42.02
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	56700000	USD
CY2020Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	1613824	shares
CY2019	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	6113038	shares
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	287700000	USD
CY2018	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	3797800	shares
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	202600000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12700000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	13300000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	10100000	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	30.07
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	19.59
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	373220	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	61.62
CY2020	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	6200000	USD
CY2019	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	6400000	USD
CY2018	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	4400000	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2728350	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	37.64
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2432689	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	33.05
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2263126	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	27.73
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	798970	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	42.50
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	557045	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	49.49
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	662215	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	11544	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2432689	shares
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	249840	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	18.55
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	176302	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	22.93
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	79451	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	48.98
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	54.02
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	27355	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	47.95
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2785654	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	43.01
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2728350	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	37.64
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	33.05
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	1529464	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	40.35
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	1820743	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	1665184	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	24.52
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	21300000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	7700000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	6800000	USD
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P8Y
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue	35300000	USD
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P6Y
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P6Y
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P6Y
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	23700000	USD
CY2019Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares	907607	shares
CY2019Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue	52.82
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	798970	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	42.50
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares	416432	shares
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue	53.20
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Options Forfeited Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares	33955	shares
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Options Forfeited Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue	49.06
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares	1256190	shares
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue	46.23
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	8.17
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	10.83
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	14.80
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y8M12D
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y6M
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y8M12D
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.015
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.027
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.029
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.021
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.016
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.010
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.237
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.228
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.221
CY2020	aos	Percentage Match Of First One Percent Of Contributions Made By Participating Employees PercentageMatchOfFirstOnePercentOfContributionsMadeByParticipatingEmployees	1
CY2020	aos	Percentage Match Of Next Five Percent Of Contributions Made By Participating Employees PercentageMatchOfNextFivePercentOfContributionsMadeByParticipatingEmployees	0.50
CY2020	aos	Postretirement Medical Benefits Qualifying Age PostretirementMedicalBenefitsQualifyingAge	P65Y
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-8600000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-2900000	USD
CY2020Q4	us-gaap	Defined Benefit Plan Health Care Cost Trend Rate Assumed Next Fiscal Year DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear	0.0740
CY2019Q4	us-gaap	Defined Benefit Plan Health Care Cost Trend Rate Assumed Next Fiscal Year DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear	0.0770
CY2020Q4	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate1 DefinedBenefitPlanUltimateHealthCareCostTrendRate1	0.0500
CY2019Q4	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate1 DefinedBenefitPlanUltimateHealthCareCostTrendRate1	0.0500
CY2020Q4	us-gaap	Defined Benefit Plan Weighted Average Asset Allocations DefinedBenefitPlanWeightedAverageAssetAllocations	1
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	2300000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-300000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	1700000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	1800000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	-1700000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	67100000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	66400000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	60100000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	17400000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	14800000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	15600000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	25800000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	19900000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	38600000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	5600000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	400000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-1700000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2300000	USD
CY2019Q4	us-gaap	Defined Benefit Plan Weighted Average Asset Allocations DefinedBenefitPlanWeightedAverageAssetAllocations	1
CY2020Q4	us-gaap	Defined Benefit Plan Fair Value Of Plan Assets DefinedBenefitPlanFairValueOfPlanAssets	857300000	USD
CY2020Q4	aos	Defined Benefit Plan Fair Value Of Non Investment Plan Assets DefinedBenefitPlanFairValueOfNonInvestmentPlanAssets	1500000	USD
CY2020Q4	aos	Defined Benefit Plan Fair Value Of Plan Assets Including Noninvestment Plan Assets DefinedBenefitPlanFairValueOfPlanAssetsIncludingNoninvestmentPlanAssets	858800000	USD
CY2019Q4	us-gaap	Defined Benefit Plan Fair Value Of Plan Assets DefinedBenefitPlanFairValueOfPlanAssets	828900000	USD
CY2019Q4	aos	Defined Benefit Plan Fair Value Of Non Investment Plan Assets DefinedBenefitPlanFairValueOfNonInvestmentPlanAssets	3400000	USD
CY2019Q4	aos	Defined Benefit Plan Fair Value Of Plan Assets Including Noninvestment Plan Assets DefinedBenefitPlanFairValueOfPlanAssetsIncludingNoninvestmentPlanAssets	832300000	USD
CY2020	us-gaap	Defined Benefit Plan Contributions By Employer DefinedBenefitPlanContributionsByEmployer	0	USD
CY2020Q4	us-gaap	Defined Benefit Plan Expected Future Employer Contributions Next Fiscal Year DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear	0	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	1500000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-19200000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-1200000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-500000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	99000000.0	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	102100000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113600000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.035
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.028
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.024
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.005
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.005
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Percent EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent	-0.009
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Percent EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent	-0.005
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Percent EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent	-0.004
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.009
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.223
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.216
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.204
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	407300000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	400300000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	376000000.0	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	36600000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	71800000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	181800000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	443900000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	472100000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	557800000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	114100000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	116600000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	116400000	USD
CY2020Q4	aos	Taxes Payable On Foreign Earnings Not Permanently Reinvested TaxesPayableOnForeignEarningsNotPermanentlyReinvested	9800000	USD
CY2020	aos	Cash And Cash Equivalents And Marketable Securities Were Held By Foreign Subsidiaries CashAndCashEquivalentsAndMarketableSecuritiesWereHeldByForeignSubsidiaries	524200000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	21600000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	27300000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Warranty Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsWarrantyReserves	42500000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Warranty Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsWarrantyReserves	39700000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	34900000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	13000000.0	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	36300000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Inventory DeferredTaxAssetsInventory	1500000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Inventory Costs DeferredTaxLiabilitiesDeferredExpenseCapitalizedInventoryCosts	300000	USD
CY2020Q4	aos	Deferred Tax Assets Accounts Receivable DeferredTaxAssetsAccountsReceivable	16300000	USD
CY2019Q4	aos	Deferred Tax Assets Accounts Receivable DeferredTaxAssetsAccountsReceivable	16300000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	66200000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	61300000	USD
CY2020Q4	aos	Deferred Tax Asset Environmental DeferredTaxAssetEnvironmental	1900000	USD
CY2019Q4	aos	Deferred Tax Asset Environmental DeferredTaxAssetEnvironmental	1900000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	9800000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	20800000	USD
CY2020Q4	aos	Deferred Tax Asset Tax Loss And Credit Carryovers DeferredTaxAssetTaxLossAndCreditCarryovers	20300000	USD
CY2019Q4	aos	Deferred Tax Asset Tax Loss And Credit Carryovers DeferredTaxAssetTaxLossAndCreditCarryovers	15200000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	9900000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	7700000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	11900000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	101000000.0	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	112300000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	96200000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	117300000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	11300000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	21100000	USD
CY2019Q4	aos	Net Operating Losses And Tax Credits NetOperatingLossesAndTaxCredits	15200000	USD
CY2018Q4	aos	Net Operating Losses And Tax Credits NetOperatingLossesAndTaxCredits	17500000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	11900000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	13100000	USD
CY2020	aos	Net Operating Losses And Tax Credits Increase Decrease Amount NetOperatingLossesAndTaxCreditsIncreaseDecreaseAmount	5100000	USD
CY2019	aos	Net Operating Losses And Tax Credits Increase Decrease Amount NetOperatingLossesAndTaxCreditsIncreaseDecreaseAmount	-2300000	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	1100000	USD
CY2019	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-1200000	USD
CY2020Q4	aos	Net Operating Losses And Tax Credits NetOperatingLossesAndTaxCredits	20300000	USD
CY2019Q4	aos	Net Operating Losses And Tax Credits NetOperatingLossesAndTaxCredits	15200000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	13000000.0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	11900000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	9700000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	8300000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	700000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1400000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	9000000.0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	9700000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	500000	USD
CY2019	aos	Maximum Aggregate Product Liability Insurance Coverage MaximumAggregateProductLiabilityInsuranceCoverage	125000000	USD
CY2020	aos	Maximum Aggregate Product Liability Insurance Coverage MaximumAggregateProductLiabilityInsuranceCoverage	125000000	USD
CY2020Q4	aos	Product Liability Individual Claim Maximum Amount ProductLiabilityIndividualClaimMaximumAmount	7500000	USD
CY2019Q4	aos	Product Liability Individual Claim Maximum Amount ProductLiabilityIndividualClaimMaximumAmount	7500000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2895300000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	557800000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	99000000.0	USD
CY2020Q4	us-gaap	Purchase Obligation PurchaseObligation	157200000	USD
CY2020Q4	aos	Distributor Rebate Accruals DistributorRebateAccruals	5400000	USD
CY2019Q4	aos	Distributor Rebate Accruals DistributorRebateAccruals	14100000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2992700000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3187900000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	503200000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	529100000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	613400000	USD
CY2020	us-gaap	Interest Expense InterestExpense	7300000	USD
CY2019	us-gaap	Interest Expense InterestExpense	11000000.0	USD
CY2018	us-gaap	Interest Expense InterestExpense	8400000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	443900000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	472100000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	102100000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	113600000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	344900000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	370000000.0	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	444200000	USD
CY2020Q4	us-gaap	Assets Assets	3160700000	USD
CY2019Q4	us-gaap	Assets Assets	3058000000.0	USD
CY2018Q4	us-gaap	Assets Assets	3071500000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	80000000.0	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	78300000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	71900000	USD
CY2020	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	56800000	USD
CY2019	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	64400000	USD
CY2018	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	85200000	USD
CY2020Q4	us-gaap	Noncurrent Assets NoncurrentAssets	672000000.0	USD
CY2019Q4	us-gaap	Noncurrent Assets NoncurrentAssets	673200000	USD
CY2018Q4	us-gaap	Noncurrent Assets NoncurrentAssets	625900000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2895300000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2992700000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3187900000	USD
CY2020Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	636900000	USD
CY2019Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	748200000	USD
CY2020Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	663900000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	765400000	USD
CY2020Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	760000000.0	USD
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	728200000	USD
CY2020Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	834500000	USD
CY2019Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	750900000	USD
CY2020Q1	us-gaap	Gross Profit GrossProfit	239500000	USD
CY2019Q1	us-gaap	Gross Profit GrossProfit	292800000	USD
CY2020Q2	us-gaap	Gross Profit GrossProfit	247500000	USD
CY2019Q2	us-gaap	Gross Profit GrossProfit	308700000	USD
CY2020Q3	us-gaap	Gross Profit GrossProfit	297100000	USD
CY2019Q3	us-gaap	Gross Profit GrossProfit	284200000	USD
CY2020Q4	us-gaap	Gross Profit GrossProfit	324100000	USD
CY2019Q4	us-gaap	Gross Profit GrossProfit	295000000.0	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	51700000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	89300000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	67800000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	102100000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	105400000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	87300000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	120000000.0	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	91300000	USD
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.32
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.53
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.42
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.61
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.65
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.53
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.74
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.56
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.32
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.53
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.42
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.61
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.65
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.53
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.74
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.56
CY2020Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.24
CY2019Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.22
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.24
CY2019Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.22
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.24
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.22
CY2020Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.26
CY2019Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.24
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	7700000	USD

Files In Submission

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$AOS
A O Smith Corp Stock $aos

2020 Q4 Form 10-K Financial Statement

#000009114221000025 Filed on February 12, 2021

Income Statement

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Facts In Submission

Files In Submission

$AOS A O Smith Corp Stock $aos

2020 Q4 Form 10-K Financial Statement

#000009114221000025 Filed on February 12, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AOS
A O Smith Corp Stock $aos