$CNA
CNA FINANCIAL CORP Stock $cna

$cna Overview Financials Valuation SEC Filings Company Website

2023 Q1 Form 10-K Financial Statement

#000002117523000006 Filed on February 07, 2023

Income Statement

Concept	2023 Q1	2022 Q4	2022
Revenue	$3.152B	$3.111B	$11.88B
YoY Change	9.25%	1.87%	-0.24%
Cost Of Revenue	$1.646B		$6.361B
YoY Change	13.6%		0.54%
Gross Profit	$1.506B		$5.518B
YoY Change	4.87%		-1.13%
Gross Profit Margin	47.78%		46.45%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$12.00M	$13.00M	$51.00M
YoY Change	-7.69%	0.0%	-5.56%
% of Gross Profit	0.8%		0.92%
Operating Expenses	$2.753B	$2.789B	$10.69B
YoY Change	11.05%	3.45%	3.64%
Operating Profit	-$1.247B		-$5.168B
YoY Change	19.56%		9.26%
Interest Expense	$28.00M	-$28.00M	$112.0M
YoY Change	0.0%	0.0%	-0.88%
% of Operating Profit
Other Income/Expense, Net	$60.00M		$291.0M
YoY Change	-4.76%		20.25%
Pretax Income	$371.0M	$294.0M	$1.081B
YoY Change	-1.85%	-10.91%	-27.16%
Income Tax	$74.00M	$46.00M	$187.0M
% Of Pretax Income	19.95%	15.65%	17.3%
Net Earnings	$297.0M	$248.0M	$894.0M
YoY Change	-5.11%	-6.77%	-25.62%
Net Earnings / Revenue	9.42%	7.97%	7.53%
Basic Earnings Per Share	$1.10		$3.29
Diluted Earnings Per Share	$1.09	$0.91	$3.28
COMMON SHARES
Basic Shares Outstanding	270.9M shares	270.9M shares	271.6M shares
Diluted Shares Outstanding	272.3M shares		272.5M shares

Balance Sheet

Concept	2023 Q1	2022 Q4	2022
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$483.0M	$475.0M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$232.0M	$226.0M	$381.0M
YoY Change	3.11%	0.0%	-4.99%
Goodwill	$145.0M	$144.0M
YoY Change	-1.36%	-2.7%
Intangibles
YoY Change
Long-Term Investments	$44.02B	$43.18B	$43.18B
YoY Change	-6.54%	-14.21%	-14.21%
Other Assets	$1.157B	$1.178B	$1.178B
YoY Change	111.52%	729.58%	729.58%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$62.06B	$60.93B	$60.93B
YoY Change	-2.72%	-8.57%	-8.57%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses			$220.0M
YoY Change			-11.29%
Deferred Revenue
YoY Change
Short-Term Debt	$243.0M	$243.0M	$0.00
YoY Change
Long-Term Debt Due	$243.0M	$243.0M	$243.0M
YoY Change
Total Short-Term Liabilities	$243.0M	$243.0M	$463.0M
YoY Change		-2.02%	86.69%
LONG-TERM LIABILITIES
Long-Term Debt	$2.539B	$2.538B	$2.538B
YoY Change	-8.64%	-8.67%	-8.67%
Other Long-Term Liabilities	$7.640B	$7.697B	$7.477B
YoY Change	-4.12%	0.85%	-2.03%
Total Long-Term Liabilities	$2.539B	$2.538B	$10.02B
YoY Change	-8.64%	-8.67%	-3.8%
TOTAL LIABILITIES
Total Short-Term Liabilities	$243.0M	$243.0M	$463.0M
Total Long-Term Liabilities	$2.539B	$2.538B	$10.02B
Total Liabilities	$53.39B	$52.10B	$52.10B
YoY Change	0.78%	-3.21%	-3.21%
SHAREHOLDERS EQUITY
Retained Earnings	$9.191B	$9.572B
YoY Change	-1.37%	-0.94%
Common Stock	$2.879B	$2.903B
YoY Change	0.03%	0.17%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$95.00M	$93.00M
YoY Change	23.38%	29.17%
Treasury Stock Shares	2.188M shares	2.144M shares
Shareholders Equity	$8.667B	$8.825B	$8.825B
YoY Change
Total Liabilities & Shareholders Equity	$62.06B	$60.93B	$60.93B
YoY Change	-2.72%	-8.57%	-8.57%

Cashflow Statement

Concept	2023 Q1	2022 Q4	2022
OPERATING ACTIVITIES
Net Income	$297.0M	$248.0M	$894.0M
YoY Change	-5.11%	-6.77%	-25.62%
Depreciation, Depletion And Amortization	$12.00M	$13.00M	$51.00M
YoY Change	-7.69%	0.0%	-5.56%
Cash From Operating Activities	$436.0M	$512.0M	$2.502B
YoY Change	-32.4%	-20.37%	25.29%
INVESTING ACTIVITIES
Capital Expenditures	$20.00M	$11.00M	$52.00M
YoY Change	66.67%	-210.0%	100.0%
Acquisitions
YoY Change
Other Investing Activities	$71.00M	-$429.0M	$10.00M
YoY Change	-160.68%	-30.92%	-1100.0%
Cash From Investing Activities	$51.00M	-$440.0M	-$1.512B
YoY Change	-139.53%	-30.27%	23.13%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$39.00M
YoY Change			116.67%
Debt Paid & Issued, Net			$0.00
YoY Change
Cash From Financing Activities	-$480.0M	-108.0M	-$1.032B
YoY Change	-30.23%	4.85%	59.26%
NET CHANGE
Cash From Operating Activities	$436.0M	512.0M	$2.502B
Cash From Investing Activities	$51.00M	-440.0M	-$1.512B
Cash From Financing Activities	-$480.0M	-108.0M	-$1.032B
Net Change In Cash	$8.000M	-36.00M	-$61.00M
YoY Change	-104.57%	-60.44%	-152.14%
FREE CASH FLOW
Cash From Operating Activities	$436.0M	$512.0M	$2.502B
Capital Expenditures	$20.00M	$11.00M	$52.00M
Free Cash Flow	$416.0M	$501.0M	$2.450B
YoY Change	-34.28%	-23.28%	24.3%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2022	dei	Entity Central Index Key EntityCentralIndexKey	0000021175
CY2022	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2022
CY2022	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2022	dei	Amendment Flag AmendmentFlag	false
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherAssets
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherAssets
CY2022Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilities
CY2021Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilities
CY2022	us-gaap	Fair Value Recurring Basis Unobservable Input Reconciliation Asset Gain Loss Statement Of Income Extensible List FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList	http://www.cna.com/20221231#InvestmentsandDerivativesRealizedGainLoss
CY2022	us-gaap	Fair Value Recurring Basis Unobservable Input Reconciliation Asset Gain Loss Statement Of Other Comprehensive Income Extensible List FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfOtherComprehensiveIncomeExtensibleList	http://fasb.org/us-gaap/2022#OtherComprehensiveIncomeLossNetOfTax
CY2021	us-gaap	Fair Value Recurring Basis Unobservable Input Reconciliation Asset Gain Loss Statement Of Income Extensible List FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList	http://www.cna.com/20221231#InvestmentsandDerivativesRealizedGainLoss
CY2021	us-gaap	Fair Value Recurring Basis Unobservable Input Reconciliation Asset Gain Loss Statement Of Other Comprehensive Income Extensible List FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfOtherComprehensiveIncomeExtensibleList	http://fasb.org/us-gaap/2022#OtherComprehensiveIncomeLossNetOfTax
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CY2022Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P12M
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CY2022Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
CY2022	dei	Document Type DocumentType	10-K
CY2022	dei	Document Annual Report DocumentAnnualReport	true
CY2022	dei	Document Period End Date DocumentPeriodEndDate	2022-12-31
CY2022	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2022	dei	Document Transition Report DocumentTransitionReport	false
CY2022	dei	Entity File Number EntityFileNumber	1-5823
CY2022	dei	Entity Registrant Name EntityRegistrantName	CNA FINANCIAL CORPORATION
CY2022	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2022	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	36-6169860
CY2022	dei	Entity Address Address Line1 EntityAddressAddressLine1	151 N. Franklin
CY2022	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	60606
CY2022	dei	Entity Address City Or Town EntityAddressCityOrTown	Chicago,
CY2022	dei	Entity Address State Or Province EntityAddressStateOrProvince	IL
CY2022	dei	City Area Code CityAreaCode	312
CY2022	dei	Local Phone Number LocalPhoneNumber	822-5000
CY2022	dei	Security12b Title Security12bTitle	Common Stock, Par value $2.50
CY2022	dei	Trading Symbol TradingSymbol	"CNA"
CY2022	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2022	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2022	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2022	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2022	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2022	dei	Entity Small Business EntitySmallBusiness	false
CY2022	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2022	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2022	dei	Entity Shell Company EntityShellCompany	false
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CY2022Q2	dei	Entity Public Float EntityPublicFloat	1239000000	usd
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CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	255000000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	226000000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	226000000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	144000000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	148000000	usd
CY2022Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	3671000000	usd
CY2021Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	3476000000	usd
CY2022Q4	us-gaap	Other Assets OtherAssets	2274000000	usd
CY2021Q4	us-gaap	Other Assets OtherAssets	2261000000	usd
CY2022Q4	us-gaap	Assets Assets	60927000000	usd
CY2021Q4	us-gaap	Assets Assets	66639000000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	25099000000	usd
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	24174000000	usd
CY2022Q4	us-gaap	Unearned Premiums UnearnedPremiums	6374000000	usd
CY2021Q4	us-gaap	Unearned Premiums UnearnedPremiums	5761000000	usd
CY2022Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	10151000000	usd
CY2021Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	13236000000	usd
CY2022Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	243000000	usd
CY2021Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	0	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2538000000	usd
CY2021Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2779000000	usd
CY2022Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	4714000000	usd
CY2021Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	4503000000	usd
CY2022Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	26000000	usd
CY2021Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	56000000	usd
CY2022Q4	us-gaap	Other Liabilities OtherLiabilities	2983000000	usd
CY2021Q4	us-gaap	Other Liabilities OtherLiabilities	3377000000	usd
CY2022Q4	us-gaap	Liabilities Liabilities	52102000000	usd
CY2021Q4	us-gaap	Liabilities Liabilities	53830000000	usd
CY2021Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2021Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	2.50
CY2022Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	2.50
CY2021Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2022Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2021Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	273040243	shares
CY2022Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	273040243	shares
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	270895902	shares
CY2021Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	271363999	shares
CY2022Q4	us-gaap	Common Stock Value CommonStockValue	683000000	usd
CY2021Q4	us-gaap	Common Stock Value CommonStockValue	683000000	usd
CY2022Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	2220000000	usd
CY2021Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	2215000000	usd
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	9572000000	usd
CY2021Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	9663000000	usd
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-3557000000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	320000000	usd
CY2022Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	2144341	shares
CY2021Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	1676244	shares
CY2022Q4	us-gaap	Treasury Stock Value TreasuryStockValue	93000000	usd
CY2021Q4	us-gaap	Treasury Stock Value TreasuryStockValue	72000000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	8825000000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	12809000000	usd
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	60927000000	usd
CY2021Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	66639000000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	894000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1202000000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	690000000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-34000000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	47000000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-49000000	usd
CY2022	us-gaap	Increase Decrease In Financial Instruments Used In Operating Activities IncreaseDecreaseInFinancialInstrumentsUsedInOperatingActivities	-6000000	usd
CY2021	us-gaap	Increase Decrease In Financial Instruments Used In Operating Activities IncreaseDecreaseInFinancialInstrumentsUsedInOperatingActivities	-20000000	usd
CY2020	us-gaap	Increase Decrease In Financial Instruments Used In Operating Activities IncreaseDecreaseInFinancialInstrumentsUsedInOperatingActivities	5000000	usd
CY2022	cna	Net Realized Investment Gains Losses Continuing And Discontinuing Operations NetRealizedInvestmentGainsLossesContinuingAndDiscontinuingOperations	-199000000	usd
CY2021	cna	Net Realized Investment Gains Losses Continuing And Discontinuing Operations NetRealizedInvestmentGainsLossesContinuingAndDiscontinuingOperations	120000000	usd
CY2020	cna	Net Realized Investment Gains Losses Continuing And Discontinuing Operations NetRealizedInvestmentGainsLossesContinuingAndDiscontinuingOperations	-54000000	usd
CY2022	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	-250000000	usd
CY2021	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	127000000	usd
CY2020	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	8000000	usd
CY2022	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	129000000	usd
CY2021	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	81000000	usd
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	67000000	usd
CY2022	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	51000000	usd
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	54000000	usd
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	60000000	usd
CY2022	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	226000000	usd
CY2021	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	1358000000	usd
CY2020	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	409000000	usd
CY2022	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	29000000	usd
CY2021	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	-3000000	usd
CY2020	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	-16000000	usd
CY2022	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	79000000	usd
CY2021	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	30000000	usd
CY2020	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	43000000	usd
CY2022	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	1791000000	usd
CY2021	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	2463000000	usd
CY2020	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	1681000000	usd
CY2022	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-192000000	usd
CY2021	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-76000000	usd
CY2020	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-145000000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2502000000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1997000000	usd
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1775000000	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	5909000000	usd
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	3816000000	usd
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	5904000000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2358000000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	4464000000	usd
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	3760000000	usd
CY2022	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	509000000	usd
CY2021	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	316000000	usd
CY2020	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	355000000	usd
CY2022	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	138000000	usd
CY2021	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	246000000	usd
CY2020	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	373000000	usd
CY2022	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	125000000	usd
CY2021	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	190000000	usd
CY2020	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	74000000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	9821000000	usd
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	9307000000	usd
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	10269000000	usd
CY2022	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	294000000	usd
CY2021	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	304000000	usd
CY2020	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	452000000	usd
CY2022	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	337000000	usd
CY2021	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	440000000	usd
CY2020	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	224000000	usd
CY2022	us-gaap	Payments To Acquire Mortgage Notes Receivable PaymentsToAcquireMortgageNotesReceivable	200000000	usd
CY2021	us-gaap	Payments To Acquire Mortgage Notes Receivable PaymentsToAcquireMortgageNotesReceivable	95000000	usd
CY2020	us-gaap	Payments To Acquire Mortgage Notes Receivable PaymentsToAcquireMortgageNotesReceivable	172000000	usd
CY2022	cna	Change In Other Investments ChangeInOtherInvestments	8000000	usd
CY2021	cna	Change In Other Investments ChangeInOtherInvestments	-6000000	usd
CY2020	cna	Change In Other Investments ChangeInOtherInvestments	-8000000	usd
CY2022	cna	Change In Short Term Investments ChangeInShortTermInvestments	155000000	usd
CY2021	cna	Change In Short Term Investments ChangeInShortTermInvestments	-83000000	usd
CY2020	cna	Change In Short Term Investments ChangeInShortTermInvestments	-39000000	usd
CY2022	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	52000000	usd
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	26000000	usd
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	23000000	usd
CY2022	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	10000000	usd
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1000000	usd
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-16000000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1512000000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1228000000	usd
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-705000000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	982000000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	621000000	usd
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	950000000	usd
CY2022	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	usd
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	usd
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	495000000	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	usd
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	usd
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	419000000	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	39000000	usd
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	18000000	usd
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	18000000	usd
CY2022	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-11000000	usd
CY2021	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-9000000	usd
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-10000000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1032000000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-648000000	usd
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-902000000	usd
CY2022	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-19000000	usd
CY2021	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-4000000	usd
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	9000000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-61000000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	117000000	usd
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	177000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	536000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	419000000	usd
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	242000000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	475000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	536000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	419000000	usd
CY2022	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	3.60
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.27
CY2022	cna	Structured Settlement Annuities Interest Rates Low End StructuredSettlementAnnuitiesInterestRatesLowEnd	0.064
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	3.48
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	8825000000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	12809000000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	12707000000	usd
CY2022	us-gaap	Use Of Estimates UseOfEstimates	The preparation of Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from those estimates.
CY2022Q4	cna	Anticipated Amounts Due From Insureds Related To Losses Under Deductible Policies AnticipatedAmountsDueFromInsuredsRelatedToLossesUnderDeductiblePolicies	1100000000	usd
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CY2021	cna	Structured Settlement Annuities Interest Rates Low End StructuredSettlementAnnuitiesInterestRatesLowEnd	0.064
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CY2021Q4	cna	Discounted Reserves For Unfunded Structured Settlements DiscountedReservesForUnfundedStructuredSettlements	503000000	usd
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CY2021Q4	cna	Discounted Reserves For Unfunded Structure Settlements Discount Amount DiscountedReservesForUnfundedStructureSettlementsDiscountAmount	621000000	usd
CY2022Q4	cna	Amountofinterestrecognizedonthediscountedreservesofunfundedstructuredsettlements Amountofinterestrecognizedonthediscountedreservesofunfundedstructuredsettlements	36000000	usd
CY2021Q4	cna	Amountofinterestrecognizedonthediscountedreservesofunfundedstructuredsettlements Amountofinterestrecognizedonthediscountedreservesofunfundedstructuredsettlements	36000000	usd
CY2020Q4	cna	Amountofinterestrecognizedonthediscountedreservesofunfundedstructuredsettlements Amountofinterestrecognizedonthediscountedreservesofunfundedstructuredsettlements	35000000	usd
CY2021	us-gaap	Workers Compensation Discount Percent WorkersCompensationDiscountPercent	0.035
CY2022	us-gaap	Workers Compensation Discount Percent WorkersCompensationDiscountPercent	0.035
CY2022Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	211000000	usd
CY2021Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	228000000	usd
CY2022Q4	us-gaap	Workers Compensation Discount Amount WorkersCompensationDiscountAmount	93000000	usd
CY2021Q4	us-gaap	Workers Compensation Discount Amount WorkersCompensationDiscountAmount	97000000	usd
CY2022Q4	cna	Amountofinterestaccretionrecognizedonthediscountedreservesofworkerscompensationlifetimeclaimreserves Amountofinterestaccretionrecognizedonthediscountedreservesofworkerscompensationlifetimeclaimreserves	9000000	usd
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CY2020Q4	cna	Amountofinterestaccretionrecognizedonthediscountedreservesofworkerscompensationlifetimeclaimreserves Amountofinterestaccretionrecognizedonthediscountedreservesofworkerscompensationlifetimeclaimreserves	15000000	usd
CY2022	cna	Longterm Care Claim Reserves Weighted Average Discounted Interest Rate LongtermCareClaimReservesWeightedAverageDiscountedInterestRate	0.059
CY2021	cna	Longterm Care Claim Reserves Weighted Average Discounted Interest Rate LongtermCareClaimReservesWeightedAverageDiscountedInterestRate	0.058
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CY2021Q4	cna	Discountedreservesforlongtermcareclaimreserves Discountedreservesforlongtermcareclaimreserves	2700000000	usd
CY2022Q4	cna	Discountedreservesforlongtermcareclaimreservesdiscountamount Discountedreservesforlongtermcareclaimreservesdiscountamount	450000000	usd
CY2021Q4	cna	Discountedreservesforlongtermcareclaimreservesdiscountamount Discountedreservesforlongtermcareclaimreservesdiscountamount	428000000	usd
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CY2021	us-gaap	Liability For Future Policy Benefit By Product Segment Interest Rate Year Of Issue LiabilityForFuturePolicyBenefitByProductSegmentInterestRateYearOfIssue	0.053
CY2022	us-gaap	Liability For Future Policy Benefit By Product Segment Interest Rate Year Of Issue LiabilityForFuturePolicyBenefitByProductSegmentInterestRateYearOfIssue	0.053
CY2022	us-gaap	Loss Contingency Undiscounted Amount Of Insurance Related Assessment Liability LossContingencyUndiscountedAmountOfInsuranceRelatedAssessmentLiability	74000000	usd
CY2021	us-gaap	Loss Contingency Undiscounted Amount Of Insurance Related Assessment Liability LossContingencyUndiscountedAmountOfInsuranceRelatedAssessmentLiability	79000000	usd
CY2022	cna	Percentage Of Billed Receivables Compared To Total Reinsurance Receivable PercentageOfBilledReceivablesComparedToTotalReinsuranceReceivable	0.05
CY2022	us-gaap	Policyholder Dividends Rate On Policy Earnings PolicyholderDividendsRateOnPolicyEarnings	0.02
CY2021	us-gaap	Policyholder Dividends Rate On Policy Earnings PolicyholderDividendsRateOnPolicyEarnings	0.01
CY2020	us-gaap	Policyholder Dividends Rate On Policy Earnings PolicyholderDividendsRateOnPolicyEarnings	0.01
CY2022	cna	Increasedecreaseinshadowadjustmentnetoftax Increasedecreaseinshadowadjustmentnetoftax	-2416000000	usd
CY2021	cna	Increasedecreaseinshadowadjustmentnetoftax Increasedecreaseinshadowadjustmentnetoftax	-296000000	usd
CY2022Q4	cna	Reduction Of Net Unrealized Gains On Investments Included In Aoci Due To Shadow Adjustments ReductionOfNetUnrealizedGainsOnInvestmentsIncludedInAOCIDueToShadowAdjustments	61000000	usd
CY2021Q4	cna	Reduction Of Net Unrealized Gains On Investments Included In Aoci Due To Shadow Adjustments ReductionOfNetUnrealizedGainsOnInvestmentsIncludedInAOCIDueToShadowAdjustments	2477000000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-22000000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-1000000	usd
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	13000000	usd
CY2022	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	1000000	shares
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	1000000	shares
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	1000000	shares
CY2022	us-gaap	Interest Paid Net InterestPaidNet	109000000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	110000000	usd
CY2020	us-gaap	Interest Paid Net InterestPaidNet	124000000	usd
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	277000000	usd
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	278000000	usd
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	108000000	usd
CY2022	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	1877000000	usd
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CY2021	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	64000000	usd
CY2020	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	64000000	usd
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CY2021	us-gaap	Net Investment Income NetInvestmentIncome	2159000000	usd
CY2020	us-gaap	Net Investment Income NetInvestmentIncome	1935000000	usd
CY2022Q4	cna	Non Income Producing Fixed Maturity Securities NonIncomeProducingFixedMaturitySecurities	0	usd
CY2021Q4	cna	Non Income Producing Fixed Maturity Securities NonIncomeProducingFixedMaturitySecurities	1000000	usd
CY2022Q4	cna	Non Income Producing Mortgage Loans NonIncomeProducingMortgageLoans	7000000	usd
CY2021Q4	cna	Non Income Producing Mortgage Loans NonIncomeProducingMortgageLoans	7000000	usd
CY2022Q4	cna	Investmentsthat Exceed Ten Percentof Stockholders Equity InvestmentsthatExceedTenPercentofStockholdersEquity	0	usd
CY2021Q4	cna	Investmentsthat Exceed Ten Percentof Stockholders Equity InvestmentsthatExceedTenPercentofStockholdersEquity	0	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	120000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	186000000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	220000000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	261000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	90000000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	220000000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-141000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	96000000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	0	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-116000000	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	4000000	usd
CY2020	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-3000000	usd
CY2022	us-gaap	Gain Loss On Sale Of Derivatives GainLossOnSaleOfDerivatives	64000000	usd
CY2021	us-gaap	Gain Loss On Sale Of Derivatives GainLossOnSaleOfDerivatives	6000000	usd
CY2020	us-gaap	Gain Loss On Sale Of Derivatives GainLossOnSaleOfDerivatives	-10000000	usd
CY2022	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	8000000	usd
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-10000000	usd
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	21000000	usd
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CY2021	cna	Realized Gain Losson Short Term Investments RealizedGainLossonShortTermInvestments	4000000	usd
CY2020	cna	Realized Gain Losson Short Term Investments RealizedGainLossonShortTermInvestments	-20000000	usd
CY2022	cna	Investmentsand Derivatives Realized Gain Loss InvestmentsandDerivativesRealizedGainLoss	-199000000	usd
CY2021	cna	Investmentsand Derivatives Realized Gain Loss InvestmentsandDerivativesRealizedGainLoss	120000000	usd
CY2020	cna	Investmentsand Derivatives Realized Gain Loss InvestmentsandDerivativesRealizedGainLoss	-54000000	usd
CY2022	cna	Investment And Derivative Realized Gain Loss Coinsurance Agreement InvestmentAndDerivativeRealizedGainLossCoinsuranceAgreement	18000000	usd
CY2022	cna	Investment And Derivative Realized Gain Loss Coinsurance Agreement InvestmentAndDerivativeRealizedGainLossCoinsuranceAgreement	18000000	usd
CY2020	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-20000000	usd
CY2022	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	62000000	usd
CY2021	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	31000000	usd
CY2020	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	111000000	usd
CY2022	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	8000000	usd
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-10000000	usd
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	21000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	41032000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	652000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	4056000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	1000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	37627000000	usd
CY2022Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	0	usd
CY2022Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	0	usd
CY2022Q4	cna	Debt Securities Amortized Cost DebtSecuritiesAmortizedCost	41032000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	652000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	4056000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	1000000	usd
CY2022Q4	us-gaap	Debt Securities DebtSecurities	37627000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	39945000000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	4558000000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	112000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	18000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	44373000000	usd
CY2021Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	7000000	usd
CY2021Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	7000000	usd
CY2021Q4	cna	Debt Securities Amortized Cost DebtSecuritiesAmortizedCost	39952000000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	4558000000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	112000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	18000000	usd
CY2021Q4	us-gaap	Debt Securities DebtSecurities	44380000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	25234000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	2946000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	4277000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1110000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	29511000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	4056000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	5695000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	92000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	370000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	20000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	6065000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	112000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	29511000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	4056000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	6065000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	112000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	18000000	usd
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	0	usd
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Purchased With Credit Deterioration Increase DebtSecuritiesAvailableForSaleAllowanceForCreditLossPurchasedWithCreditDeteriorationIncrease	3000000	usd
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	0	usd
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Writeoff DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff	12000000	usd
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-8000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	1000000	usd
CY2020Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	40000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	14000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Purchased With Credit Deterioration Increase DebtSecuritiesAvailableForSaleAllowanceForCreditLossPurchasedWithCreditDeteriorationIncrease	11000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	24000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Writeoff DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff	16000000	usd
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-7000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	18000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	1012000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	1001000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	1603000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	1624000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	9880000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	9399000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	10637000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	11229000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	13788000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	12453000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	13294000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	14338000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	16352000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	14774000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	14411000000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	17182000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	41032000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	37627000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	39945000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	44373000000	usd
CY2022Q4	cna	Limited Partnership Investments LimitedPartnershipInvestments	1926000000	usd
CY2021Q4	cna	Limited Partnership Investments LimitedPartnershipInvestments	1859000000	usd
CY2022Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	176000000	usd
CY2021Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	266000000	usd
CY2022Q4	cna	Percentage Of Limited Partnerships Reported On Current Basis PercentageOfLimitedPartnershipsReportedOnCurrentBasis	0.26
CY2022Q4	cna	Percentage Of Limited Partnerships Reported On One Month Lag PercentageOfLimitedPartnershipsReportedOnOneMonthLag	0.05
CY2022	cna	Increase Decrease Short Term Investments IncreaseDecreaseShortTermInvestments	-4000000	usd
CY2022Q4	cna	Limited Partnerships Invested In Private Debt And Equity LimitedPartnershipsInvestedInPrivateDebtAndEquity	0.76
CY2021Q4	cna	Limited Partnerships Invested In Private Debt And Equity LimitedPartnershipsInvestedInPrivateDebtAndEquity	0.68
CY2022Q4	cna	Percentage Of Limited Partnerships Employing Hedge Fund Strategies Focused On Fixed Income And Equity Investments PercentageOfLimitedPartnershipsEmployingHedgeFundStrategiesFocusedOnFixedIncomeAndEquityInvestments	0.24
CY2021Q4	cna	Percentage Of Limited Partnerships Employing Hedge Fund Strategies Focused On Fixed Income And Equity Investments PercentageOfLimitedPartnershipsEmployingHedgeFundStrategiesFocusedOnFixedIncomeAndEquityInvestments	0.32
CY2022Q4	cna	Carrying Value Of Ten Largest Limited Partnerships CarryingValueOfTenLargestLimitedPartnerships	633000000	usd
CY2021Q4	cna	Carrying Value Of Ten Largest Limited Partnerships CarryingValueOfTenLargestLimitedPartnerships	665000000	usd
CY2021Q4	cna	Carrying Value Of Limited Partnerships As Percentage Of Aggregate Partnership Equity CarryingValueOfLimitedPartnershipsAsPercentageOfAggregatePartnershipEquity	0.01
CY2022Q4	cna	Carrying Value Of Limited Partnerships As Percentage Of Aggregate Partnership Equity CarryingValueOfLimitedPartnershipsAsPercentageOfAggregatePartnershipEquity	0.01
CY2022Q4	cna	Income As Percentage Of Change In Partnership Equity For All Limited Partnerships IncomeAsPercentageOfChangeInPartnershipEquityForAllLimitedPartnerships	0.02
CY2021Q4	cna	Income As Percentage Of Change In Partnership Equity For All Limited Partnerships IncomeAsPercentageOfChangeInPartnershipEquityForAllLimitedPartnerships	0.02
CY2020Q4	cna	Income As Percentage Of Change In Partnership Equity For All Limited Partnerships IncomeAsPercentageOfChangeInPartnershipEquityForAllLimitedPartnerships	0.02
CY2022Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	1000000	usd
CY2022Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	0	usd
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CY2021Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	0	usd
CY2021Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	270000000	usd
CY2021Q4	us-gaap	Other Liabilities Fair Value Disclosure OtherLiabilitiesFairValueDisclosure	12000000	usd
CY2022	cna	Increase Decrease Fixed Maturity Securities IncreaseDecreaseFixedMaturitySecurities	-224000000	usd
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CY2022	cna	Increase Decrease Funds Withheld Liability IncreaseDecreaseFundsWithheldLiability	-216000000	usd
CY2022Q4	us-gaap	Embedded Derivative Fair Value Of Embedded Derivative Liability EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability	14000000	usd
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CY2022Q4	cna	Commitments To Sell Various Privately Placed Debt Securities CommitmentsToSellVariousPrivatelyPlacedDebtSecurities	60000000	usd
CY2022Q4	cna	Carrying Value Of Securities Deposited Under Requirements Of Regulatory Authorities CarryingValueOfSecuritiesDepositedUnderRequirementsOfRegulatoryAuthorities	2800000000	usd
CY2021Q4	cna	Carrying Value Of Securities Deposited Under Requirements Of Regulatory Authorities CarryingValueOfSecuritiesDepositedUnderRequirementsOfRegulatoryAuthorities	3000000000	usd
CY2022Q4	cna	Cash And Securities Deposited As Collateral For Letters Of Credit CashAndSecuritiesDepositedAsCollateralForLettersOfCredit	900000000	usd
CY2021Q4	cna	Cash And Securities Deposited As Collateral For Letters Of Credit CashAndSecuritiesDepositedAsCollateralForLettersOfCredit	1200000000	usd
CY2022Q4	us-gaap	Debt Securities DebtSecurities	37627000000	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	674000000	usd
CY2022Q4	cna	Shortterm Investmentsand Other ShorttermInvestmentsandOther	1679000000	usd
CY2022Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	39980000000	usd
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CY2022Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	1000000	usd
CY2021Q4	us-gaap	Debt Securities DebtSecurities	44380000000	usd
CY2021Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	1035000000	usd
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CY2021Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	1578000000	usd
CY2022	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	1000000	usd
CY2022	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-323000000	usd
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CY2022	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	580000000	usd
CY2022	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	10000000	usd
CY2022	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	145000000	usd
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CY2022Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	1676000000	usd
CY2022	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-4000000	usd
CY2022	cna	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Includedin Other Comprehensive Income Loss FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisAssetUnrealizedGainLossIncludedinOtherComprehensiveIncomeLoss	-321000000	usd
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CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-12000000	usd
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-43000000	usd
CY2021	cna	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings And Other Comprehensive Income Loss FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarningsAndOtherComprehensiveIncomeLoss	-46000000	usd
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	612000000	usd
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CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	130000000	usd
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	150000000	usd
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	127000000	usd
CY2021Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	1578000000	usd
CY2021	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-2000000	usd
CY2021	cna	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Includedin Other Comprehensive Income Loss FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisAssetUnrealizedGainLossIncludedinOtherComprehensiveIncomeLoss	-44000000	usd
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CY2021Q4	cna	Other Invested Assets Overseas Deposit OtherInvestedAssetsOverseasDeposit	74000000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	usd
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CY2021	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	0	usd
CY2020	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	0	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	0	usd
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	227000000	usd
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	312000000	usd
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CY2022	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	41000000	usd
CY2021	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	51000000	usd
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CY2022	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-15000000	usd
CY2021	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	3000000	usd
CY2020	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-2000000	usd
CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	10000000	usd
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	13000000	usd
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6000000	usd
CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	6000000	usd
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	5000000	usd
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CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	282000000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	131000000	usd
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CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	235000000	usd
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CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	187000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	282000000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	131000000	usd
CY2022	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	1000000	usd
CY2021	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	18000000	usd
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CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	124000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	45000000	usd
CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	-10000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	188000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	173000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	190000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	193000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	64000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	64000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	35000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	46000000	usd
CY2022Q4	cna	Deferred Tax Assets Deferred Retroactive Reinsurance Benefit DeferredTaxAssetsDeferredRetroactiveReinsuranceBenefit	89000000	usd
CY2021Q4	cna	Deferred Tax Assets Deferred Retroactive Reinsurance Benefit DeferredTaxAssetsDeferredRetroactiveReinsuranceBenefit	90000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	706000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	116000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	88000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1388000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	654000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	59000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	93000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	113000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	99000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	272000000	usd
CY2022Q4	cna	Deferred Tax Liabilities Deferred Expense Softwareand Hardware DeferredTaxLiabilitiesDeferredExpenseSoftwareandHardware	21000000	usd
CY2021Q4	cna	Deferred Tax Liabilities Deferred Expense Softwareand Hardware DeferredTaxLiabilitiesDeferredExpenseSoftwareandHardware	27000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	17000000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	21000000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	210000000	usd
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	512000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	1178000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	142000000	usd
CY2022Q4	us-gaap	Tax Credit Carryforward Amount TaxCreditCarryforwardAmount	0	usd
CY2022Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	0	usd
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	19908000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	5191000000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	25099000000	usd
CY2022	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following table presents a reconciliation between beginning and ending claim and claim adjustment expense reserves, including claim and claim adjustment expense reserves of the Life & Group segment.</span></div><div style="margin-top:5pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"/><td style="width:64.066%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:9.733%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.966%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:9.733%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.966%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:9.736%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">As of or for the years ended December 31</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(In millions)</span></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2022</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2021</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Reserves, beginning of year:</span></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Gross</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">24,174 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">22,706 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">21,720 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Ceded</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,969 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,005 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">3,835 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net reserves, beginning of year</span></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">19,205 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">18,701 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">17,885 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Reduction of net reserves due to Excess Workers' Compensation Loss Portfolio Transfer</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(632)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net incurred claim and claim adjustment expenses:</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Provision for insured events of current year</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">6,243 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5,970 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5,793 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Increase (decrease) in provision for insured events of prior years</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(187)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(104)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(119)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Amortization of discount</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">170 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">174 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">183 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total net incurred </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(1)</span></div></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">6,226 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">6,040 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5,857 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net payments attributable to:</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Current year events</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(913)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(1,014)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(948)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Prior year events</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(4,348)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(3,830)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(4,216)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total net payments</span></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(5,261)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(4,844)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(5,164)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Foreign currency translation adjustment and other</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(262)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(60)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">123 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net reserves, end of year</span></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">19,908 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">19,205 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">18,701 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Ceded reserves, end of year</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5,191 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,969 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,005 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Gross reserves, end of year</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">25,099 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">24,174 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">22,706 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div><div style="margin-top:1pt;padding-left:13.5pt;text-align:justify;text-indent:-13.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(1) Total net incurred above does not agree to Insurance claims and policyholders' benefits as reflected on the Consolidated Statements of Operations due to amounts related to retroactive reinsurance deferred gain accounting, the loss on the Excess Workers' Compensation LPT, uncollectible reinsurance and benefit expenses related to future policy benefits, which are not reflected in the table above.</span></div>
CY2021Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	24174000000	usd
CY2020Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	22706000000	usd
CY2019Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	21720000000	usd
CY2021Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	4969000000	usd
CY2020Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	4005000000	usd
CY2019Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	3835000000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	19205000000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	18701000000	usd
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	17885000000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Opening Balance Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseOpeningBalanceAdjustments	0	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Opening Balance Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseOpeningBalanceAdjustments	-632000000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Opening Balance Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseOpeningBalanceAdjustments	0	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	6243000000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	5970000000	usd
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	5793000000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-187000000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-104000000	usd
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-119000000	usd
CY2022	cna	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims Amortization Of Discount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaimsAmortizationOfDiscount	170000000	usd
CY2021	cna	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims Amortization Of Discount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaimsAmortizationOfDiscount	174000000	usd
CY2020	cna	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims Amortization Of Discount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaimsAmortizationOfDiscount	183000000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	6226000000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	6040000000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	5857000000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	913000000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1014000000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	948000000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	4348000000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	3830000000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	4216000000	usd
CY2022	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	5261000000	usd
CY2021	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	4844000000	usd
CY2020	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	5164000000	usd
CY2022	cna	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Cta And Other LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCtaAndOther	-262000000	usd
CY2021	cna	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Cta And Other LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCtaAndOther	-60000000	usd
CY2020	cna	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Cta And Other LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCtaAndOther	123000000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	19908000000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	19205000000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	18701000000	usd
CY2022Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	5191000000	usd
CY2021Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	4969000000	usd
CY2020Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	4005000000	usd
CY2022Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	25099000000	usd
CY2021Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	24174000000	usd
CY2020Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	22706000000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Reported Claims Amount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseReportedClaimsAmount	10387000000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred But Not Reported Ibnr Claims Amount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsAmount	14712000000	usd
CY2022Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	25099000000	usd
CY2022Q4	cna	Net Case Reserves NetCaseReserves	8319000000	usd
CY2022Q4	cna	Net Ibnr Reserves NetIbnrReserves	11589000000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	19908000000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Reported Claims Amount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseReportedClaimsAmount	10555000000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred But Not Reported Ibnr Claims Amount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsAmount	13619000000	usd
CY2021Q4	cna	Liabilityforunpaidclaimandclaimadjustmentexpensegross Liabilityforunpaidclaimandclaimadjustmentexpensegross	24174000000	usd
CY2021Q4	cna	Net Case Reserves NetCaseReserves	8369000000	usd
CY2021Q4	cna	Net Ibnr Reserves NetIbnrReserves	10836000000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	19205000000	usd
CY2022	cna	Pretax Favorable Unfavorable Premium Development Excluding Life Group PretaxFavorableUnfavorablePremiumDevelopmentExcludingLifeGroup	-32000000	usd
CY2021	cna	Pretax Favorable Unfavorable Premium Development Excluding Life Group PretaxFavorableUnfavorablePremiumDevelopmentExcludingLifeGroup	11000000	usd
CY2020	cna	Pretax Favorable Unfavorable Premium Development Excluding Life Group PretaxFavorableUnfavorablePremiumDevelopmentExcludingLifeGroup	-20000000	usd
CY2021Q1	us-gaap	Funds Held Under Reinsurance Agreements Liability FundsHeldUnderReinsuranceAgreementsLiability	690000000	usd
CY2021Q1	cna	Retroactive Reinsurance Agreement Maximum RetroactiveReinsuranceAgreementMaximum	1000000000	usd
CY2021Q1	cna	Reinsurance Premiums Paid ReinsurancePremiumsPaid	697000000	usd
	cna	Reinsurance Premiums Paid ReinsurancePremiumsPaid	64000000	usd
CY2021Q1	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	12000000	usd
CY2022Q4	us-gaap	Securities Held As Collateral At Fair Value SecuritiesHeldAsCollateralAtFairValue	608000000	usd
CY2022Q3	cna	Liability For Unpaid Claims And Claims Adjustment Expense Long Term Care Policies Period Increase Decrease LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseLongTermCarePoliciesPeriodIncreaseDecrease	-25000000	usd
CY2022Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred But Not Reported Ibnr Claims Amount LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsAmount	107000000	usd
CY2022Q3	cna	Liability For Unpaid Claims And Claims Adjustment Expense Claim Severity Adjustment Period Increase Decrease LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimSeverityAdjustmentPeriodIncreaseDecrease	-82000000	usd
CY2022Q3	cna	Liability For Unpaid Claims And Claims Adjustment Expense Structured Settlement Obligations Period Increase Decrease LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseStructuredSettlementObligationsPeriodIncreaseDecrease	-5000000	usd
CY2021Q3	cna	Liability For Unpaid Claims And Claims Adjustment Expense Long Term Care Policies Period Increase Decrease LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseLongTermCarePoliciesPeriodIncreaseDecrease	-40000000	usd
CY2021Q3	cna	Liability For Unpaid Claims And Claims Adjustment Expense Structured Settlement Obligations Period Increase Decrease LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseStructuredSettlementObligationsPeriodIncreaseDecrease	2000000	usd
CY2022Q3	cna	Liability For Future Policy Benefits Gross Premium Valuation Pretax Margin LiabilityForFuturePolicyBenefitsGrossPremiumValuationPretaxMargin	125000000	usd
CY2021Q3	cna	Liability For Future Policy Benefits Gross Premium Valuation Pretax Margin LiabilityForFuturePolicyBenefitsGrossPremiumValuationPretaxMargin	72000000	usd
CY2022Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	5191000000	usd
CY2021Q4	cna	Ceded Claim And Claim Adjustment Expenses CededClaimAndClaimAdjustmentExpenses	4969000000	usd
CY2022Q4	cna	Ceded Future Policy Benefits CededFuturePolicyBenefits	0	usd
CY2021Q4	cna	Ceded Future Policy Benefits CededFuturePolicyBenefits	288000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables On Paid Losses Gross ReinsuranceRecoverablesOnPaidLossesGross	247000000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Paid Losses Gross ReinsuranceRecoverablesOnPaidLossesGross	227000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	5438000000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	5484000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	22000000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	21000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	5416000000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	5463000000	usd
CY2022Q4	cna	Voluntary Reinsurance Recoverable Gross VoluntaryReinsuranceRecoverableGross	4808000000	usd
CY2022Q4	us-gaap	Funds Held Under Reinsurance Agreements Liability FundsHeldUnderReinsuranceAgreementsLiability	3700000000	usd
CY2021Q4	us-gaap	Funds Held Under Reinsurance Agreements Liability FundsHeldUnderReinsuranceAgreementsLiability	4000000000	usd
CY2022	us-gaap	Direct Premiums Earned DirectPremiumsEarned	13524000000	usd
CY2022	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	277000000	usd
CY2022	us-gaap	Ceded Premiums Earned CededPremiumsEarned	5134000000	usd
CY2022	us-gaap	Premiums Earned Net PremiumsEarnedNet	8667000000	usd
CY2021	us-gaap	Direct Premiums Earned DirectPremiumsEarned	12997000000	usd
CY2021	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	288000000	usd
CY2021	us-gaap	Ceded Premiums Earned CededPremiumsEarned	5110000000	usd
CY2021	us-gaap	Premiums Earned Net PremiumsEarnedNet	8175000000	usd
CY2020	us-gaap	Direct Premiums Earned DirectPremiumsEarned	12001000000	usd
CY2020	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	288000000	usd
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	4640000000	usd
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	7649000000	usd
CY2022	us-gaap	Direct Premiums Written DirectPremiumsWritten	14264000000	usd
CY2022	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	281000000	usd
CY2022	us-gaap	Ceded Premiums Written CededPremiumsWritten	5417000000	usd
CY2022	us-gaap	Premiums Written Net PremiumsWrittenNet	9128000000	usd
CY2021	us-gaap	Direct Premiums Written DirectPremiumsWritten	13587000000	usd
CY2021	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	303000000	usd
CY2021	us-gaap	Ceded Premiums Written CededPremiumsWritten	5485000000	usd
CY2021	us-gaap	Premiums Written Net PremiumsWrittenNet	8405000000	usd
CY2020	us-gaap	Direct Premiums Written DirectPremiumsWritten	12612000000	usd
CY2020	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	279000000	usd
CY2020	us-gaap	Ceded Premiums Written CededPremiumsWritten	4832000000	usd
CY2020	us-gaap	Premiums Written Net PremiumsWrittenNet	8059000000	usd
CY2022	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	2631000000	usd
CY2021	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	3058000000	usd
CY2020	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	3158000000	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2538000000	usd
CY2021Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2779000000	usd
CY2022Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	2781000000	usd
CY2021Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	2779000000	usd
CY2022Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	5000000	usd
CY2022Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Maximum Amount Available FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresMaximumAmountAvailable	106000000	usd
CY2022Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	0	usd
CY2021Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	0	usd
CY2019	us-gaap	Debt Instrument Term DebtInstrumentTerm	P5Y
CY2019Q4	us-gaap	Line Of Credit Facility Current Borrowing Capacity LineOfCreditFacilityCurrentBorrowingCapacity	250000000	usd
CY2019Q4	cna	Line Of Credit Facility Additional Borrowing Capacity LineOfCreditFacilityAdditionalBorrowingCapacity	100000000	usd
CY2019Q4	cna	Lineof Credit Facility Numberof Extension Options LineofCreditFacilityNumberofExtensionOptions	2	extensionterm
CY2019	cna	Line Of Credit Facility Extension Term LineOfCreditFacilityExtensionTerm	P1Y
CY2022Q4	us-gaap	Minimum Net Worth Required For Compliance MinimumNetWorthRequiredForCompliance	8700000000	usd
CY2021Q4	us-gaap	Line Of Credit LineOfCredit	0	usd
CY2022Q4	us-gaap	Line Of Credit LineOfCredit	0	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	243000000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	550000000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	500000000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	500000000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1000000000	usd
CY2022Q4	us-gaap	Debt Instrument Unamortized Discount DebtInstrumentUnamortizedDiscount	12000000	usd
CY2022Q4	us-gaap	Long Term Debt LongTermDebt	2781000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	0	usd
CY2022	us-gaap	Defined Benefit Plan Actuarial Gain Loss DefinedBenefitPlanActuarialGainLoss	514000000	usd
CY2021	us-gaap	Defined Benefit Plan Actuarial Gain Loss DefinedBenefitPlanActuarialGainLoss	84000000	usd
CY2022Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Accumulated Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation	49000000	usd
CY2021Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Accumulated Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation	61000000	usd
CY2022Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Fair Value Of Plan Assets DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets	0	usd
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-12000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	262000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-67000000	usd
CY2022	cna	Other Comprehensive Income Loss Pensionand Other Postretirement Benefit Plans Settlementsbefore Tax OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansSettlementsbeforeTax	0	usd
CY2021	cna	Other Comprehensive Income Loss Pensionand Other Postretirement Benefit Plans Settlementsbefore Tax OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansSettlementsbeforeTax	1000000	usd
CY2020	cna	Other Comprehensive Income Loss Pensionand Other Postretirement Benefit Plans Settlementsbefore Tax OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansSettlementsbeforeTax	3000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	0	usd
CY2021	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	0	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-30000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-46000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-45000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-18000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-309000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	19000000	usd
CY2022	cna	Assumptionsusedincalculatingassumedhealthcarecosttrendrate Assumptionsusedincalculatingassumedhealthcarecosttrendrate	0.04
CY2022	cna	Assumptionsusedincalculatingassumedhealthcarecosttrendrate Assumptionsusedincalculatingassumedhealthcarecosttrendrate	0.04
CY2022Q4	cna	Future Capital Call Commitments FutureCapitalCallCommitments	120000000	usd
CY2022	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Percent DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent	0.50
CY2022	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent Of Match DefinedContributionPlanEmployerMatchingContributionPercentOfMatch	1
CY2022	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.06
CY2022	cna	Company Contributionof Eligible Compensation Dependingon Age Percent CompanyContributionofEligibleCompensationDependingonAgePercent	0.05
CY2022	cna	Defined Contribution Plan Employers Matching Contribution Vesting Periodin Years DefinedContributionPlanEmployersMatchingContributionVestingPeriodinYears	P5Y
CY2022	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	71000000	usd
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	65000000	usd
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	70000000	usd
CY2022Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	16000000	shares
CY2022Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	4800000	shares
CY2022	cna	Measurement Periodof Specific Annual Performance Goalsin Years MeasurementPeriodofSpecificAnnualPerformanceGoalsinYears	P1Y
CY2022	cna	Cliff Vesting Period Following Dateof Grant CliffVestingPeriodFollowingDateofGrant	P2Y
CY2022	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	36000000	usd
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	32000000	usd
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	37000000	usd
CY2022	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8000000	usd
CY2021	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	6000000	usd
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	6000000	usd
CY2022Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	44000000	usd
CY2022	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y8M12D
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	35000000	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	36000000	usd
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	35000000	usd
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	46.78
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	45.82
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	34.36
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	2375598	shares
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	41.21
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$CNA
CNA FINANCIAL CORP Stock $cna

2023 Q1 Form 10-K Financial Statement

#000002117523000006 Filed on February 07, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CNA CNA FINANCIAL CORP Stock $cna

2023 Q1 Form 10-K Financial Statement

#000002117523000006 Filed on February 07, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CNA
CNA FINANCIAL CORP Stock $cna