$AWK
American Water Works Company, Inc. Stock $awk

$awk Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000141063622000048 Filed on February 16, 2022

Income Statement

Concept	2021 Q4	2021 Q3	2021
Revenue	$951.0M	$1.092B	$3.930B
YoY Change	3.03%	1.2%	4.05%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$160.0M	$161.0M	$636.0M
YoY Change	4.58%	4.55%	5.3%
% of Gross Profit
Operating Expenses	$731.0M	$675.0M	$2.734B
YoY Change	10.76%	4.49%	8.11%
Operating Profit	$220.0M	$417.0M	$1.196B
YoY Change	-16.35%	-3.7%	-4.17%
Interest Expense	-$99.00M	-$101.0M	-$399.0M
YoY Change	0.0%	2.02%	1.01%
% of Operating Profit	-45.0%	-24.22%	-33.36%
Other Income/Expense, Net	$26.00M	-$77.00M	$444.0M
YoY Change	52.94%	-4.94%	-237.04%
Pretax Income	$894.0M	$340.0M	$1.640B
YoY Change	393.92%	-3.41%	77.49%
Income Tax	$249.0M	$62.00M	$377.0M
% Of Pretax Income	27.85%	18.24%	22.99%
Net Earnings	$645.0M	$278.0M	$1.263B
YoY Change	344.83%	5.3%	78.14%
Net Earnings / Revenue	67.82%	25.46%	32.14%
Basic Earnings Per Share	$3.55	$1.53	$6.96
Diluted Earnings Per Share	$3.55	$1.53	$6.95
COMMON SHARES
Basic Shares Outstanding	181.5M shares	182.0M shares	182.0M shares
Diluted Shares Outstanding		182.0M shares	182.0M shares

Balance Sheet

Concept	2021 Q4	2021 Q3	2021
SHORT-TERM ASSETS
Cash & Short-Term Investments	$116.0M	$70.00M	$116.0M
YoY Change	-78.79%	-87.5%	-78.79%
Cash & Equivalents	$116.0M	$70.00M	$116.0M
Short-Term Investments
Other Short-Term Assets	$159.0M	$162.0M	$1.039B
YoY Change	25.2%	14.08%	6.24%
Inventory	$57.00M	$53.00M	$57.00M
Prepaid Expenses
Receivables	$271.0M	$348.0M	$342.0M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$1.554B	$1.590B	$1.554B
YoY Change	-18.47%	-19.17%	-18.47%
LONG-TERM ASSETS
Property, Plant & Equipment	$21.18B	$20.59B	$21.18B
YoY Change	7.44%	6.84%	6.92%
Goodwill	$1.139B	$1.511B
YoY Change	-24.27%	0.47%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$242.0M	$202.0M	$1.486B
YoY Change	23.47%	0.0%	7.84%
Total Long-Term Assets	$24.52B	$23.74B	$24.52B
YoY Change	7.27%	5.87%	7.27%
TOTAL ASSETS
Total Short-Term Assets	$1.554B	$1.590B	$1.554B
Total Long-Term Assets	$24.52B	$23.74B	$24.52B
Total Assets	$26.08B	$25.33B	$26.08B
YoY Change	5.29%	3.85%	5.29%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$235.0M	$175.0M	$235.0M
YoY Change	24.34%	8.02%	24.34%
Accrued Expenses	$701.0M	$520.0M	$789.0M
YoY Change	18.61%	2.97%	16.2%
Deferred Revenue
YoY Change
Short-Term Debt	$584.0M	$684.0M	$584.0M
YoY Change	-54.45%	-34.48%	-54.45%
Long-Term Debt Due	$57.00M	$48.00M	$57.00M
YoY Change	-82.67%	-28.36%	-82.67%
Total Short-Term Liabilities	$2.141B	$1.844B	$2.141B
YoY Change	-25.69%	-18.41%	-25.69%
LONG-TERM LIABILITIES
Long-Term Debt	$10.34B	$10.35B	$10.34B
YoY Change	10.83%	8.01%	10.83%
Other Long-Term Liabilities	$180.0M	$180.0M	$3.871B
YoY Change	116.87%	127.85%	-2.86%
Total Long-Term Liabilities	$180.0M	$180.0M	$14.22B
YoY Change	116.87%	127.85%	6.74%
TOTAL LIABILITIES
Total Short-Term Liabilities	$2.141B	$1.844B	$2.141B
Total Long-Term Liabilities	$180.0M	$180.0M	$14.22B
Total Liabilities	$2.321B	$2.024B	$18.78B
YoY Change	-21.69%	-13.47%	2.54%
SHAREHOLDERS EQUITY
Retained Earnings	$925.0M	$500.0M
YoY Change	806.86%	218.47%
Common Stock	$6.783B	$6.774B
YoY Change	0.5%	0.49%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$365.0M	$363.0M
YoY Change	4.89%	4.31%
Treasury Stock Shares	5.269M shares	5.260M shares
Shareholders Equity	$7.298B	$6.866B	$7.298B
YoY Change
Total Liabilities & Shareholders Equity	$26.08B	$25.33B	$26.08B
YoY Change	5.29%	3.85%	5.29%

Cashflow Statement

Concept	2021 Q4	2021 Q3	2021
OPERATING ACTIVITIES
Net Income	$645.0M	$278.0M	$1.263B
YoY Change	344.83%	5.3%	78.14%
Depreciation, Depletion And Amortization	$160.0M	$161.0M	$636.0M
YoY Change	4.58%	4.55%	5.3%
Cash From Operating Activities	$412.0M	$509.0M	$1.441B
YoY Change	-5.94%	11.38%	1.05%
INVESTING ACTIVITIES
Capital Expenditures	-$559.0M	$453.0M	$1.764B
YoY Change	10.04%	2.03%	-3.18%
Acquisitions			$135.0M
YoY Change			0.0%
Other Investing Activities	$376.0M	-$66.00M	$228.0M
YoY Change	-451.4%	50.0%	-195.4%
Cash From Investing Activities	-$183.0M	-$519.0M	-$1.536B
YoY Change	-70.24%	6.35%	-25.47%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$0.00
YoY Change
Debt Paid & Issued, Net			$372.0M
YoY Change			8.77%
Cash From Financing Activities	-193.0M	6.000M	-$345.0M
YoY Change	-225.32%	-76.0%	-130.8%
NET CHANGE
Cash From Operating Activities	412.0M	509.0M	$1.441B
Cash From Investing Activities	-183.0M	-519.0M	-$1.536B
Cash From Financing Activities	-193.0M	6.000M	-$345.0M
Net Change In Cash	36.00M	-4.000M	-$440.0M
YoY Change	-256.52%	-33.33%	-190.72%
FREE CASH FLOW
Cash From Operating Activities	$412.0M	$509.0M	$1.441B
Capital Expenditures	-$559.0M	$453.0M	$1.764B
Free Cash Flow	$971.0M	$56.00M	-$323.0M
YoY Change	2.64%	330.77%	-18.43%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2021	dei	Entity Central Index Key EntityCentralIndexKey	0001410636
CY2021	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
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CY2021	dei	Document Type DocumentType	10-K
CY2021	dei	Document Annual Report DocumentAnnualReport	true
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Entity File Number EntityFileNumber	001-34028
CY2021	dei	Entity Registrant Name EntityRegistrantName	AMERICAN WATER WORKS COMPANY, INC.
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	51-0063696
CY2021	dei	Entity Address Address Line1 EntityAddressAddressLine1	1 Water Street
CY2021	dei	Entity Address City Or Town EntityAddressCityOrTown	Camden
CY2021	dei	Entity Address State Or Province EntityAddressStateOrProvince	NJ
CY2021	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	08102-1658
CY2021	dei	City Area Code CityAreaCode	856
CY2021	dei	Local Phone Number LocalPhoneNumber	955-4001
CY2021	dei	Security12b Title Security12bTitle	Common stock, par value $0.01 per share
CY2021	dei	Trading Symbol TradingSymbol	AWK
CY2021	dei	Security Exchange Name SecurityExchangeName	NYSE
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CY2021	awk	Benefit Costs Non Operating Net BenefitCostsNonOperatingNet	-78000000	USD
CY2020	awk	Benefit Costs Non Operating Net BenefitCostsNonOperatingNet	-49000000	USD
CY2019	awk	Benefit Costs Non Operating Net BenefitCostsNonOperatingNet	-16000000	USD
CY2021	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	747000000	USD
CY2020	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-44000000	USD
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	18000000	USD
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	22000000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	29000000	USD
CY2021	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	444000000	USD
CY2020	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-324000000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-381000000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1640000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	924000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	833000000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	377000000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	215000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	212000000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1263000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	709000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	621000000	USD
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.96
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.91
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.44
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.95
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.91
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.43
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	182000000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	181000000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	181000000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	182000000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	182000000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	181000000	shares
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1263000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	709000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	621000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	4000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-3000000	USD
CY2021	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	1000000	USD
CY2020	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	12000000	USD
CY2019	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-8000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-1000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-1000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-1000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-4000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-3000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-4000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-1000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	1000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	-1000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	-5000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	1000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-4000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-13000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	4000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-13000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-2000000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1267000000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	696000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	619000000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1263000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	709000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	621000000	USD
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	636000000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	604000000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	582000000	USD
CY2021	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	230000000	USD
CY2020	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	207000000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	208000000	USD
CY2021	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	37000000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	34000000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	28000000	USD
CY2021	awk	Gain Loss On Disposition Of Business Including Utilities Operating Expense Income Other GainLossOnDispositionOfBusinessIncludingUtilitiesOperatingExpenseIncomeOther	747000000	USD
CY2020	awk	Gain Loss On Disposition Of Business Including Utilities Operating Expense Income Other GainLossOnDispositionOfBusinessIncludingUtilitiesOperatingExpenseIncomeOther	0	USD
CY2019	awk	Gain Loss On Disposition Of Business Including Utilities Operating Expense Income Other GainLossOnDispositionOfBusinessIncludingUtilitiesOperatingExpenseIncomeOther	-34000000	USD
CY2021	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	-41000000	USD
CY2020	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	-14000000	USD
CY2019	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	17000000	USD
CY2021	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	23000000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	20000000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	41000000	USD
CY2021	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	74000000	USD
CY2020	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	97000000	USD
CY2019	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	25000000	USD
CY2021	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	40000000	USD
CY2020	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	39000000	USD
CY2019	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	31000000	USD
CY2021	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	66000000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-2000000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	66000000	USD
CY2021	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	-134000000	USD
CY2020	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	-44000000	USD
CY2019	us-gaap	Increase Decrease In Other Current Assets And Liabilities Net IncreaseDecreaseInOtherCurrentAssetsAndLiabilitiesNet	76000000	USD
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1441000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1426000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1383000000	USD
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1764000000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1822000000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1654000000	USD
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	135000000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	135000000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	235000000	USD
CY2021	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	472000000	USD
CY2020	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	2000000	USD
CY2019	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	48000000	USD
CY2021	us-gaap	Payments For Proceeds From Removal Costs PaymentsForProceedsFromRemovalCosts	109000000	USD
CY2020	us-gaap	Payments For Proceeds From Removal Costs PaymentsForProceedsFromRemovalCosts	106000000	USD
CY2019	us-gaap	Payments For Proceeds From Removal Costs PaymentsForProceedsFromRemovalCosts	104000000	USD
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1536000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2061000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1945000000	USD
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1118000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1334000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1530000000	USD
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	372000000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	342000000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	495000000	USD
CY2021	awk	Proceeds Repayment From Term Loan ProceedsRepaymentFromTermLoan	-500000000	USD
CY2020	awk	Proceeds Repayment From Term Loan ProceedsRepaymentFromTermLoan	500000000	USD
CY2019	awk	Proceeds Repayment From Term Loan ProceedsRepaymentFromTermLoan	0	USD
CY2021	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	-198000000	USD
CY2020	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	-5000000	USD
CY2019	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	-178000000	USD
CY2021	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	18000000	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	17000000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	11000000	USD
CY2021	awk	Proceeds Remittances Issuance Of Shares Share Based Payment Arrangement Including Option Exercised ProceedsRemittancesIssuanceOfSharesShareBasedPaymentArrangementIncludingOptionExercised	-1000000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	36000000	USD
CY2020	awk	Proceeds Remittances Issuance Of Shares Share Based Payment Arrangement Including Option Exercised ProceedsRemittancesIssuanceOfSharesShareBasedPaymentArrangementIncludingOptionExercised	9000000	USD
CY2019	awk	Proceeds Remittances Issuance Of Shares Share Based Payment Arrangement Including Option Exercised ProceedsRemittancesIssuanceOfSharesShareBasedPaymentArrangementIncludingOptionExercised	15000000	USD
CY2021	us-gaap	Repayments Of Construction Loans Payable RepaymentsOfConstructionLoansPayable	25000000	USD
CY2020	us-gaap	Repayments Of Construction Loans Payable RepaymentsOfConstructionLoansPayable	24000000	USD
CY2019	us-gaap	Repayments Of Construction Loans Payable RepaymentsOfConstructionLoansPayable	30000000	USD
CY2021	us-gaap	Proceeds From Advances For Construction ProceedsFromAdvancesForConstruction	62000000	USD
CY2020	us-gaap	Proceeds From Advances For Construction ProceedsFromAdvancesForConstruction	28000000	USD
CY2019	us-gaap	Proceeds From Advances For Construction ProceedsFromAdvancesForConstruction	26000000	USD
CY2021	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	26000000	USD
CY2020	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	15000000	USD
CY2019	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	15000000	USD
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	428000000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	389000000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	353000000	USD
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-345000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1120000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	494000000	USD
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-440000000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	485000000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-68000000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	576000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	91000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	159000000	USD
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	136000000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	576000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	91000000	USD
CY2021	us-gaap	Interest Paid Net InterestPaidNet	389000000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	382000000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	383000000	USD
CY2021	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	6000000	USD
CY2020	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	2000000	USD
CY2019	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	4000000	USD
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1000000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	7000000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	12000000	USD
CY2021	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	292000000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	221000000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	235000000	USD
CY2021	awk	Noncash Or Part Noncash Disposal Notes Receivable NoncashOrPartNoncashDisposalNotesReceivable	720000000	USD
CY2020	awk	Noncash Or Part Noncash Disposal Notes Receivable NoncashOrPartNoncashDisposalNotesReceivable	0	USD
CY2019	awk	Noncash Or Part Noncash Disposal Notes Receivable NoncashOrPartNoncashDisposalNotesReceivable	0	USD
CY2021	awk	Noncash Or Part Noncash Disposal Contingent Cash Payment NoncashOrPartNoncashDisposalContingentCashPayment	75000000	USD
CY2020	awk	Noncash Or Part Noncash Disposal Contingent Cash Payment NoncashOrPartNoncashDisposalContingentCashPayment	0	USD
CY2019	awk	Noncash Or Part Noncash Disposal Contingent Cash Payment NoncashOrPartNoncashDisposalContingentCashPayment	0	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	5864000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	621000000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	38000000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	36000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-2000000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.00
CY2019	us-gaap	Dividends Cash DividendsCash	362000000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	6121000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	709000000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	37000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-13000000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.20
CY2020	us-gaap	Dividends Cash DividendsCash	400000000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	6454000000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1263000000	USD
CY2021	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	17000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	4000000	USD
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.41
CY2021	us-gaap	Dividends Cash DividendsCash	440000000	USD
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	7298000000	USD
CY2021	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:3pt;margin-top:18pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-bottom:18pt;margin-top:3pt;text-align:justify;text-indent:27pt"><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 (“GAAP”) requires that management make estimates, assumptions and judgments that could affect the Company’s financial condition, results of operations and cash flows. Actual results could differ from these estimates, assumptions and judgments. The Company considers its critical accounting estimates to include (i) the application of regulatory accounting principles and the related determination and estimation of regulatory assets and liabilities, (ii) revenue recognition and the estimates used in the calculation of unbilled revenue, (iii) accounting for income taxes, (iv) benefit plan assumptions and (v) the estimates and judgments used in determining loss contingencies. The Company’s critical accounting estimates that are particularly sensitive to change in the near term are amounts reported for regulatory assets and liabilities, income taxes, benefit plan assumptions and contingency-related obligations.</span></div>
CY2021Q4	awk	Repayment Of Advances For Construction RepaymentOfAdvancesForConstruction	23000000	USD
CY2020Q4	awk	Repayment Of Advances For Construction RepaymentOfAdvancesForConstruction	23000000	USD
CY2021	awk	Amortization Of Contributions In Aid Of Construction AmortizationOfContributionsInAidOfConstruction	36000000	USD
CY2020	awk	Amortization Of Contributions In Aid Of Construction AmortizationOfContributionsInAidOfConstruction	32000000	USD
CY2019	awk	Amortization Of Contributions In Aid Of Construction AmortizationOfContributionsInAidOfConstruction	29000000	USD
CY2021	awk	Contractwith Customer Payment Term From Billing Period ContractwithCustomerPaymentTermFromBillingPeriod	P30D
CY2021	us-gaap	Accrual For Environmental Loss Contingencies Payments1 AccrualForEnvironmentalLossContingenciesPayments1	1000000	USD
CY2021Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	0	USD
CY2020Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	1000000	USD
CY2021	us-gaap	Derivatives Reporting Of Derivative Activity DerivativesReportingOfDerivativeActivity	<div style="margin-bottom:3pt;margin-top:18pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Derivative Financial Instruments</span></div><div style="margin-bottom:12pt;margin-top:3pt;text-align:justify;text-indent:27pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company uses derivative financial instruments primarily for purposes of hedging exposures to fluctuations in interest rates. These derivative contracts are entered into for periods consistent with the related underlying exposures and do not constitute positions independent of those exposures. The Company does not enter into derivative contracts for speculative purposes and does not use leveraged instruments.</span></div><div style="margin-bottom:12pt;margin-top:12pt;text-align:justify;text-indent:27pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">All derivatives are recognized on the balance sheet at fair value. On the date the derivative contract is entered into, the Company may designate the derivative as a hedge of the fair value of a recognized asset or liability (fair-value hedge) or a hedge of a forecasted transaction or of the variability of cash flows to be received or paid related to a recognized asset or liability (cash-flow hedge).</span></div><div style="margin-bottom:12pt;margin-top:12pt;text-align:justify;text-indent:27pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Changes in the fair value of a fair-value hedge, along with the gain or loss on the underlying hedged item, are recorded in current-period earnings. The gains and losses on the effective portion of cash-flow hedges are recorded in other comprehensive income, until earnings are affected by the variability of cash flows. Any ineffective portion of designated cash-flow hedges is recognized in current-period earnings.</span></div>Cash flows from derivative contracts are included in net cash provided by operating activities on the Consolidated Statements of Cash Flows.
CY2021	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	ReclassificationsCertain reclassifications have been made to prior periods in the Consolidated Financial Statements and Notes to conform to the current presentation.
CY2019	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-44000000	USD
CY2021	awk	Public Utilities General Rate Case Authorizations PublicUtilitiesGeneralRateCaseAuthorizations	115000000	USD
CY2020	awk	Public Utilities General Rate Case Authorizations PublicUtilitiesGeneralRateCaseAuthorizations	72000000	USD
CY2019	awk	Public Utilities General Rate Case Authorizations PublicUtilitiesGeneralRateCaseAuthorizations	41000000	USD
CY2021	awk	Public Utilities Infrastructure Surcharge Authorizations PublicUtilitiesInfrastructureSurchargeAuthorizations	65000000	USD
CY2020	awk	Public Utilities Infrastructure Surcharge Authorizations PublicUtilitiesInfrastructureSurchargeAuthorizations	72000000	USD
CY2019	awk	Public Utilities Infrastructure Surcharge Authorizations PublicUtilitiesInfrastructureSurchargeAuthorizations	51000000	USD
CY2021Q4	awk	Regulatory Asset Earned Revenue Percentage RegulatoryAssetEarnedRevenuePercentage	0.50
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3914000000	USD
CY2021	us-gaap	Other Operating Income OtherOperatingIncome	16000000	USD
CY2021Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1051000000	USD
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1127000000	USD
CY2021Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	1600000000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	1770000000	USD
CY2021Q4	awk	Number Of Proceedings Number Of Subsidiaries Effected Amortization Of Net Excess Accumulated Deferred Income Taxes NumberOfProceedingsNumberOfSubsidiariesEffectedAmortizationOfNetExcessAccumulatedDeferredIncomeTaxes	12	subsidiary
CY2021Q4	awk	Number Of Proceedings Number Of Subsidiaries Effected Pending Amortization Of Net Excess Accumulated Deferred Income Taxes NumberOfProceedingsNumberOfSubsidiariesEffectedPendingAmortizationOfNetExcessAccumulatedDeferredIncomeTaxes	1	subsidiary
CY2021	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3930000000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3743000000	USD
CY2020	us-gaap	Other Operating Income OtherOperatingIncome	34000000	USD
CY2020	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3777000000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3587000000	USD
CY2019	us-gaap	Other Operating Income OtherOperatingIncome	23000000	USD
CY2019	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3610000000	USD
CY2021Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	71000000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	39000000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	13000000	USD
CY2021	awk	Contractwith Customer Asset Additions ContractwithCustomerAssetAdditions	71000000	USD
CY2021	us-gaap	Contract With Customer Asset Reclassified To Receivable ContractWithCustomerAssetReclassifiedToReceivable	39000000	USD
CY2020	awk	Contractwith Customer Asset Additions ContractwithCustomerAssetAdditions	60000000	USD
CY2020	us-gaap	Contract With Customer Asset Reclassified To Receivable ContractWithCustomerAssetReclassifiedToReceivable	34000000	USD
CY2021Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	19000000	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	35000000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	27000000	USD
CY2021	awk	Contractwith Customer Liability Additions ContractwithCustomerLiabilityAdditions	152000000	USD
CY2021	awk	Contract With Customer Liability Revenue Recognized During The Period ContractWithCustomerLiabilityRevenueRecognizedDuringThePeriod	168000000	USD
CY2020	awk	Contractwith Customer Liability Additions ContractwithCustomerLiabilityAdditions	120000000	USD
CY2020	awk	Contract With Customer Liability Revenue Recognized During The Period ContractWithCustomerLiabilityRevenueRecognizedDuringThePeriod	112000000	USD
CY2021	awk	Number Of Assets Acquired From Business Combination And Asset Acquisition NumberOfAssetsAcquiredFromBusinessCombinationAndAssetAcquisition	23	acquisition
CY2021	awk	Business Combination And Asset Acquisition Consideration Transferred BusinessCombinationAndAssetAcquisitionConsiderationTransferred	112000000	USD
CY2021Q4	awk	Business Combination And Asset Acquisition Assets BusinessCombinationAndAssetAcquisitionAssets	114000000	USD
CY2021Q4	awk	Business Combination And Asset Acquisition Liabilities BusinessCombinationAndAssetAcquisitionLiabilities	2000000	USD
CY2020	awk	Number Of Assets Acquired From Business Combination And Asset Acquisition NumberOfAssetsAcquiredFromBusinessCombinationAndAssetAcquisition	23	acquisition
CY2020	awk	Business Combination And Asset Acquisition Consideration Transferred BusinessCombinationAndAssetAcquisitionConsiderationTransferred	135000000	USD
CY2020Q4	awk	Business Combination And Asset Acquisition Assets BusinessCombinationAndAssetAcquisitionAssets	159000000	USD
CY2020Q4	awk	Business Combination And Asset Acquisition Liabilities BusinessCombinationAndAssetAcquisitionLiabilities	29000000	USD
CY2020Q4	awk	Business Combination And Asset Acquisition Contributions In Aid Of Construction BusinessCombinationAndAssetAcquisitionContributionsInAidOfConstruction	21000000	USD
CY2020Q4	awk	Business Combination And Asset Acquisition Debt BusinessCombinationAndAssetAcquisitionDebt	7000000	USD
CY2019	awk	Number Of Assets Acquired From Business Combination And Asset Acquisition NumberOfAssetsAcquiredFromBusinessCombinationAndAssetAcquisition	21	acquisition
CY2019	awk	Business Combination And Asset Acquisition Consideration Transferred BusinessCombinationAndAssetAcquisitionConsiderationTransferred	235000000	USD
CY2019Q4	awk	Business Combination And Asset Acquisition Assets BusinessCombinationAndAssetAcquisitionAssets	237000000	USD
CY2019Q4	awk	Business Combination And Asset Acquisition Contributions In Aid Of Construction BusinessCombinationAndAssetAcquisitionContributionsInAidOfConstruction	5000000	USD
CY2021Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	934000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	837000000	USD
CY2021Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	27287000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	25408000000	USD
CY2021Q4	awk	Public Non Utilities Property Plant And Equipment Plant For Internal Operations PublicNonUtilitiesPropertyPlantAndEquipmentPlantForInternalOperations	126000000	USD
CY2020Q4	awk	Public Non Utilities Property Plant And Equipment Plant For Internal Operations PublicNonUtilitiesPropertyPlantAndEquipmentPlantForInternalOperations	211000000	USD
CY2021	awk	Property Plant And Equipment Weighted Average Useful Life PropertyPlantAndEquipmentWeightedAverageUsefulLife	P6Y
CY2021Q4	awk	Disposal Group Including Discontinued Operation Public Non Utilities Property Plant And Equipment DisposalGroupIncludingDiscontinuedOperationPublicNonUtilitiesPropertyPlantAndEquipment	0	USD
CY2020Q4	awk	Disposal Group Including Discontinued Operation Public Non Utilities Property Plant And Equipment DisposalGroupIncludingDiscontinuedOperationPublicNonUtilitiesPropertyPlantAndEquipment	5000000	USD
CY2021Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	27413000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	25614000000	USD
CY2021	us-gaap	Depreciation Depreciation	550000000	USD
CY2020	us-gaap	Depreciation Depreciation	520000000	USD
CY2019	us-gaap	Depreciation Depreciation	508000000	USD
CY2021	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.0277
CY2020	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.0282
CY2019	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.0296
CY2021	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	292000000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	221000000	USD
CY2019	us-gaap	Investment Tax Credit InvestmentTaxCredit	164000000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	60000000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	41000000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	45000000	USD
CY2021	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	37000000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	34000000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	28000000	USD
CY2021	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	17000000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	12000000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	32000000	USD
CY2021	awk	Accounts Receivable Allowance For Credit Loss Assets Held For Sale AccountsReceivableAllowanceForCreditLossAssetsHeldForSale	5000000	USD
CY2020	awk	Accounts Receivable Allowance For Credit Loss Assets Held For Sale AccountsReceivableAllowanceForCreditLossAssetsHeldForSale	3000000	USD
CY2019	awk	Accounts Receivable Allowance For Credit Loss Assets Held For Sale AccountsReceivableAllowanceForCreditLossAssetsHeldForSale	0	USD
CY2021Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	75000000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	60000000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	41000000	USD
CY2019Q4	us-gaap	Goodwill Gross GoodwillGross	3980000000	USD
CY2019Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	2440000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	1540000000	USD
CY2020	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	5000000	USD
CY2020	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	5000000	USD
CY2020	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-2000000	USD
CY2020	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-2000000	USD
CY2020Q4	us-gaap	Disposal Group Including Discontinued Operation Goodwill1 DisposalGroupIncludingDiscontinuedOperationGoodwill1	39000000	USD
CY2020Q4	us-gaap	Disposal Group Including Discontinued Operation Goodwill1 DisposalGroupIncludingDiscontinuedOperationGoodwill1	39000000	USD
CY2020Q4	us-gaap	Goodwill Gross GoodwillGross	3944000000	USD
CY2020Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	2440000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	1504000000	USD
CY2021	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-7000000	USD
CY2021	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-7000000	USD
CY2021	us-gaap	Goodwill Transfers GoodwillTransfers	12000000	USD
CY2021	us-gaap	Goodwill Transfers GoodwillTransfers	12000000	USD
CY2021	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	370000000	USD
CY2021	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	370000000	USD
CY2021Q4	us-gaap	Goodwill Gross GoodwillGross	3579000000	USD
CY2021Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	2440000000	USD
CY2021Q4	us-gaap	Goodwill Goodwill	1139000000	USD
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	9000000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	12000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	14000000	USD
CY2021	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
CY2020	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
CY2021Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	5100000	shares
CY2020	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-16000000	USD
CY2020	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-3000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-13000000	USD
CY2021	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	0	USD
CY2021	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-4000000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	4000000	USD
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	428000000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	389000000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	353000000	USD
CY2021Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.6025
CY2020Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.55
CY2019Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.50
CY2021Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.6025
CY2020Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.55
CY2019Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.50
CY2021Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.6025
CY2020Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.55
CY2019Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.50
CY2021Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.55
CY2020Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.50
CY2019Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.455
CY2021Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.6025
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	17000000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	21000000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	17000000	USD
CY2021	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4000000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5000000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4000000	USD
CY2021	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	13000000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	16000000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	13000000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	0	USD
CY2020	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	0	USD
CY2021	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	0	USD
CY2021Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	10433000000	USD
CY2020Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	9688000000	USD
CY2021Q4	awk	Debt Instrument Unamortized Discount Premium Fair Value Net DebtInstrumentUnamortizedDiscountPremiumFairValueNet	-9000000	USD
CY2020Q4	awk	Debt Instrument Unamortized Discount Premium Fair Value Net DebtInstrumentUnamortizedDiscountPremiumFairValueNet	-4000000	USD
CY2021Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	23000000	USD
CY2020Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	22000000	USD
CY2021Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	57000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	329000000	USD
CY2021Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	10344000000	USD
CY2020Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	9333000000	USD
CY2021Q4	us-gaap	Ratio Of Indebtedness To Net Capital1 RatioOfIndebtednessToNetCapital1	0.60
CY2021Q4	awk	Redeemable Debt Amount Outstanding RedeemableDebtAmountOutstanding	859000000	USD
CY2021Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0184
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	57000000	USD
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	280000000	USD
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	474000000	USD
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	597000000	USD
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	441000000	USD
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	8584000000	USD
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1118000000	USD
CY2021Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	11000000	USD
CY2021	awk	Ineffectiveness Recognized On Hedge Instruments IneffectivenessRecognizedOnHedgeInstruments	0	USD
CY2020	awk	Ineffectiveness Recognized On Hedge Instruments IneffectivenessRecognizedOnHedgeInstruments	0	USD
CY2021Q4	awk	Commercial Paper And Line Of Credit Facility Maximum Borrowing Capacity CommercialPaperAndLineOfCreditFacilityMaximumBorrowingCapacity	2250000000	USD
CY2021Q4	awk	Commercial Paper And Line Of Credit Facility Remaining Borrowing Capacity CommercialPaperAndLineOfCreditFacilityRemainingBorrowingCapacity	1590000000	USD
CY2021Q4	awk	Commercial Paper Outstanding CommercialPaperOutstanding	584000000	USD
CY2020Q4	awk	Commercial Paper Outstanding CommercialPaperOutstanding	786000000	USD
CY2021	us-gaap	Proceeds From Short Term Debt Maturing In More Than Three Months ProceedsFromShortTermDebtMaturingInMoreThanThreeMonths	0	USD
CY2021Q4	awk	Commercial Paper Maximum Borrowing Capacity CommercialPaperMaximumBorrowingCapacity	2100000000	USD
CY2021Q4	awk	Commercial Paper And Line Of Credit Facility Maximum Borrowing Capacity CommercialPaperAndLineOfCreditFacilityMaximumBorrowingCapacity	2250000000	USD
CY2021Q4	awk	Commercial Paper Outstanding CommercialPaperOutstanding	584000000	USD
CY2021Q4	awk	Commercial Paper And Line Of Credit Facility Outstanding CommercialPaperAndLineOfCreditFacilityOutstanding	660000000	USD
CY2021Q4	awk	Commercial Paper Remaining Borrowing Capacity CommercialPaperRemainingBorrowingCapacity	1516000000	USD
CY2021Q4	awk	Commercial Paper And Line Of Credit Facility Remaining Borrowing Capacity CommercialPaperAndLineOfCreditFacilityRemainingBorrowingCapacity	1590000000	USD
CY2021Q4	awk	Commercial Paper And Line Of Credit Facility Remaining Borrowing Capacity CommercialPaperAndLineOfCreditFacilityRemainingBorrowingCapacity	1590000000	USD
CY2020Q4	awk	Commercial Paper Maximum Borrowing Capacity CommercialPaperMaximumBorrowingCapacity	2100000000	USD
CY2020Q4	awk	Commercial Paper And Line Of Credit Facility Maximum Borrowing Capacity CommercialPaperAndLineOfCreditFacilityMaximumBorrowingCapacity	2250000000	USD
CY2020Q4	awk	Commercial Paper Outstanding CommercialPaperOutstanding	786000000	USD
CY2020Q4	awk	Commercial Paper And Line Of Credit Facility Outstanding CommercialPaperAndLineOfCreditFacilityOutstanding	862000000	USD
CY2020Q4	awk	Commercial Paper Remaining Borrowing Capacity CommercialPaperRemainingBorrowingCapacity	1314000000	USD
CY2020Q4	awk	Commercial Paper And Line Of Credit Facility Remaining Borrowing Capacity CommercialPaperAndLineOfCreditFacilityRemainingBorrowingCapacity	1388000000	USD
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	116000000	USD
CY2021Q4	awk	Cash Cash Equivalents And Short Term Debt Liquidity CashCashEquivalentsAndShortTermDebtLiquidity	1706000000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	547000000	USD
CY2020Q4	awk	Cash Cash Equivalents And Short Term Debt Liquidity CashCashEquivalentsAndShortTermDebtLiquidity	1935000000	USD
CY2021Q4	awk	Required Ratio Of Indebtedness To Net Capital1 RequiredRatioOfIndebtednessToNetCapital1	0.70
CY2021Q4	us-gaap	Ratio Of Indebtedness To Net Capital1 RatioOfIndebtednessToNetCapital1	0.60
CY2021	awk	Property And Capital Stock Tax PropertyAndCapitalStockTax	149000000	USD
CY2020	awk	Property And Capital Stock Tax PropertyAndCapitalStockTax	140000000	USD
CY2019	awk	Property And Capital Stock Tax PropertyAndCapitalStockTax	124000000	USD
CY2021	awk	Gross Receipts And Franchise Tax GrossReceiptsAndFranchiseTax	121000000	USD
CY2020	awk	Gross Receipts And Franchise Tax GrossReceiptsAndFranchiseTax	116000000	USD
CY2019	awk	Gross Receipts And Franchise Tax GrossReceiptsAndFranchiseTax	110000000	USD
CY2021	awk	Payroll Tax PayrollTax	39000000	USD
CY2020	awk	Payroll Tax PayrollTax	36000000	USD
CY2019	awk	Payroll Tax PayrollTax	35000000	USD
CY2021	us-gaap	Taxes Other TaxesOther	12000000	USD
CY2020	us-gaap	Taxes Other TaxesOther	11000000	USD
CY2019	us-gaap	Taxes Other TaxesOther	11000000	USD
CY2021	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	321000000	USD
CY2020	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	303000000	USD
CY2019	us-gaap	Utilities Operating Expense Taxes UtilitiesOperatingExpenseTaxes	280000000	USD
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CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
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CY2020	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	8000000	USD
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CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	215000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	212000000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
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CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.048
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.054
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CY2021	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0.016
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	0.001
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	-0.004
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	-0.001
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.230
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CY2020Q4	awk	Deferred Tax Assets Advances And Contributions DeferredTaxAssetsAdvancesAndContributions	424000000	USD
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CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	65000000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	301000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	329000000	USD
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CY2020Q4	awk	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions And Other Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensionsAndOtherPostretirementBenefits	100000000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	144000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	165000000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	944000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1083000000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	10000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	19000000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	934000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1064000000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	3087000000	USD
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CY2021Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	180000000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	216000000	USD
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	3336000000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	3226000000	USD
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CY2021Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	2402000000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	2093000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	110000000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	18000000	USD
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CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	140000000	USD
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CY2021Q4	us-gaap	Defined Benefit Plan Pension Plan With Projected Benefit Obligation In Excess Of Plan Assets Projected Benefit Obligation DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsProjectedBenefitObligation	2294000000	USD
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CY2021Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Accumulated Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation	2138000000	USD
CY2020Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Accumulated Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation	2188000000	USD
CY2021Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Fair Value Of Plan Assets DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets	1991000000	USD
CY2020Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Fair Value Of Plan Assets DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets	1990000000	USD
CY2021	awk	Reduction Of Expected Future Service Of Plan Participants ReductionOfExpectedFutureServiceOfPlanParticipants	0.10
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CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	14000000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	12000000	USD
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CY2021Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	507000000	USD
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CY2020	us-gaap	Net Income Loss NetIncomeLoss	709000000	USD
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CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	182000000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	182000000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	181000000	shares
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CY2021	us-gaap	Operating Expenses OperatingExpenses	2734000000	USD
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.04
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CY2020	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3777000000	USD
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CY2020	awk	Interest Expense Nonoperating InterestExpenseNonoperating	397000000	USD
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CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	924000000	USD
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CY2020	us-gaap	Net Income Loss NetIncomeLoss	709000000	USD
CY2020Q4	us-gaap	Assets Assets	24766000000	USD
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CY2019	us-gaap	Regulated And Unregulated Operating Revenue RegulatedAndUnregulatedOperatingRevenue	3610000000	USD
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CY2019	us-gaap	Operating Expenses OperatingExpenses	2396000000	USD
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CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	212000000	USD
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CY2019Q4	us-gaap	Assets Assets	22682000000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1654000000	USD
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CY2021Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	229000000	USD
CY2021Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	330000000	USD
CY2021Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	417000000	USD
CY2021Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	220000000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	133000000	USD
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CY2020Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	433000000	USD
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CY2020Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	239000000	USD
CY2020Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	263000000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	124000000	USD
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.80
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	176000000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	264000000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	145000000	USD
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.69
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.97
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.46
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.80
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.68
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.97
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.46

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$AWK
American Water Works Company, Inc. Stock $awk

2021 Q4 Form 10-K Financial Statement

#000141063622000048 Filed on February 16, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AWK American Water Works Company, Inc. Stock $awk

2021 Q4 Form 10-K Financial Statement

#000141063622000048 Filed on February 16, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AWK
American Water Works Company, Inc. Stock $awk