$CB
Chubb Ltd Stock $cb

$cb Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000089615920000003 Filed on February 27, 2020

Income Statement

Concept	2019 Q4	2018 Q4	2018 Q3
Revenue	$8.738B	$7.626B	$8.750B
YoY Change	14.58%	-4.85%	1.63%
Cost Of Revenue	$4.865B	$4.610B	$4.868B
YoY Change	5.53%	7.91%	-22.07%
Gross Profit	$3.873B	$3.016B	$3.882B
YoY Change	28.42%	-19.42%	64.28%
Gross Profit Margin	44.32%	39.55%	44.37%
Selling, General & Admin	$816.0M	$726.0M	$726.0M
YoY Change	12.4%	-2.94%	0.83%
% of Gross Profit	21.07%	24.07%	18.7%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$76.00M	$86.00M	$1.504B
YoY Change	-11.63%	30.3%	1.08%
% of Gross Profit	1.96%	2.85%	38.74%
Operating Expenses	$7.524B	$7.064B	$7.308B
YoY Change	6.51%	4.51%	-15.89%
Operating Profit	-$3.651B	-$4.048B	-$3.426B
YoY Change	-9.81%	34.22%	-45.84%
Interest Expense	$130.0M	$7.000M	$14.00M
YoY Change	1757.14%	-117.5%	-129.79%
% of Operating Profit
Other Income/Expense, Net	-$12.00M	-$15.00M	-$12.00M
YoY Change	-20.0%	0.0%	300.0%
Pretax Income	$1.342B	$514.0M	$1.414B
YoY Change	161.09%	-55.34%	-1012.26%
Income Tax	$169.0M	$184.0M	$183.0M
% Of Pretax Income	12.59%	35.8%	12.94%
Net Earnings	$1.173B	$355.0M	$1.231B
YoY Change	230.42%	-76.84%	-1858.57%
Net Earnings / Revenue	13.42%	4.66%	14.07%
Basic Earnings Per Share	$2.59	$0.77	$2.66
Diluted Earnings Per Share	$2.57	$0.76	$2.64
COMMON SHARES
Basic Shares Outstanding	453.2M shares	460.8M shares	463.0M shares
Diluted Shares Outstanding			466.0M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$1.537B	$1.247B	$1.053B
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	$1.900B	$1.700B
YoY Change	11.76%	30.77%
Goodwill	$15.30B	$15.27B	$15.33B
YoY Change	0.16%	-1.74%	-2.39%
Intangibles	$6.063B	$6.143B	$6.139B
YoY Change	-1.3%	-5.68%	-6.39%
Long-Term Investments	$110.6B	$101.6B	$101.8B
YoY Change	8.78%	-1.42%	-1.22%
Other Assets	$109.0M	$93.00M	$104.0M
YoY Change	17.2%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$176.9B	$167.8B	$167.7B
YoY Change	5.47%	0.45%	0.06%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$11.06B	$10.47B	$9.343B
YoY Change	5.65%	9.71%	1.85%
Accrued Expenses	$603.0M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$1.299B	$509.0M	$500.0M
YoY Change	155.21%	-49.75%	-50.98%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$19.15B	$17.42B	$16.16B
YoY Change	9.94%	6.04%	0.85%
LONG-TERM LIABILITIES
Long-Term Debt	$13.87B	$12.40B	$12.46B
YoY Change	11.88%	4.48%	4.97%
Other Long-Term Liabilities	$1.003B	$861.0M	$453.0M
YoY Change	16.49%	56.55%	-28.66%
Total Long-Term Liabilities	$14.87B	$13.26B	$12.91B
YoY Change	12.18%	6.78%	3.26%
TOTAL LIABILITIES
Total Short-Term Liabilities	$19.15B	$17.42B	$16.16B
Total Long-Term Liabilities	$14.87B	$13.26B	$12.91B
Total Liabilities	$121.6B	$117.5B	$116.8B
YoY Change	3.54%	1.39%	-0.3%
SHAREHOLDERS EQUITY
Retained Earnings	$36.14B	$31.70B	$31.49B
YoY Change	14.01%	15.38%	21.39%
Common Stock	$22.32B	$23.68B	$23.97B
YoY Change	-5.72%	-5.66%	-5.38%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$3.754B	$2.618B	$2.372B
YoY Change	43.39%	34.67%	26.37%
Treasury Stock Shares	27.81M shares	20.58M shares	18.68M shares
Shareholders Equity	$55.33B	$50.31B	$50.93B
YoY Change
Total Liabilities & Shareholders Equity	$176.9B	$167.8B	$167.7B
YoY Change	5.47%	0.45%	0.06%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018 Q3
OPERATING ACTIVITIES
Net Income	$1.173B	$355.0M	$1.231B
YoY Change	230.42%	-76.84%	-1858.57%
Depreciation, Depletion And Amortization	$76.00M	$86.00M	$1.504B
YoY Change	-11.63%	30.3%	1.08%
Cash From Operating Activities	$1.429B	$1.583B	$1.700B
YoY Change	-9.73%	44.96%	-4.01%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions
YoY Change
Other Investing Activities	-$2.344B	-$808.0M	-$867.0M
YoY Change	190.1%	-25.25%	-40.78%
Cash From Investing Activities	-$2.344B	-$808.0M	-$867.0M
YoY Change	190.1%	-25.25%	-40.78%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	973.0M	-567.0M	-775.0M
YoY Change	-271.6%	62.46%	47.06%
NET CHANGE
Cash From Operating Activities	1.429B	1.583B	1.700B
Cash From Investing Activities	-2.344B	-808.0M	-867.0M
Cash From Financing Activities	973.0M	-567.0M	-775.0M
Net Change In Cash	58.00M	208.0M	58.00M
YoY Change	-72.12%	-161.54%	-126.36%
FREE CASH FLOW
Cash From Operating Activities	$1.429B	$1.583B	$1.700B
Capital Expenditures
Free Cash Flow
YoY Change

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2017	us-gaap	Net Income Loss NetIncomeLoss	3861000000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	4718000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	6342000000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	611000000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	9039000000	USD
CY2017	cb	Equity In Earnings Of Subsidiaries EquityInEarningsOfSubsidiaries	0	USD
CY2017	cb	Net Realized Gains Losses NetRealizedGainsLosses	84000000	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	18454000000	USD
CY2017	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	676000000	USD
CY2017	cb	Policy Acquisition Costs And Administrative Expenses PolicyAcquisitionCostsAndAdministrativeExpenses	8614000000	USD
CY2017	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-607000000	USD
CY2017	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	400000000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	260000000	USD
CY2017	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	310000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-139000000	USD
CY2019	cb	Payments To Acquire Available For Sale Securities Debt Condensed PaymentsToAcquireAvailableForSaleSecuritiesDebtCondensed	25846000000	USD
CY2019	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	229000000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	531000000	USD
CY2019	cb	Proceeds From Sale Of Available For Sale Securities Debt Condensed ProceedsFromSaleOfAvailableForSaleSecuritiesDebtCondensed	13116000000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	946000000	USD
CY2019	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	1117000000	USD
CY2019	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	703000000	USD
CY2019	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	1315000000	USD
CY2019	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	1390000000	USD
CY2019	cb	Payment Of Contributions To Subsidiary PaymentOfContributionsToSubsidiary	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	29000000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	1237000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-5905000000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1354000000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1530000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2828000000	USD
CY2019	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	2817000000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	510000000	USD
CY2019	us-gaap	Payments For Securities Purchased Under Agreements To Resell PaymentsForSecuritiesPurchasedUnderAgreementsToResell	2817000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	204000000	USD
CY2019	cb	Advances To From Affiliates Financing Activities AdvancesToFromAffiliatesFinancingActivities	0	USD
CY2019	us-gaap	Cash Dividends Paid To Parent Company CashDividendsPaidToParentCompany	0	USD
CY2019	us-gaap	Proceeds From Contributions From Parent ProceedsFromContributionsFromParent	0	USD
CY2019	us-gaap	Proceeds From Repayments Of Bank Overdrafts ProceedsFromRepaymentsOfBankOverdrafts	0	USD
CY2019	us-gaap	Additions To Contract Holders Funds AdditionsToContractHoldersFunds	514000000	USD
CY2019	us-gaap	Withdrawal From Contract Holders Funds WithdrawalFromContractHoldersFunds	303000000	USD
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CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1340000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1646000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	5480000000	USD
CY2018	cb	Payments To Acquire Available For Sale Securities Debt Condensed PaymentsToAcquireAvailableForSaleSecuritiesDebtCondensed	24735000000	USD
CY2018	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	456000000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	207000000	USD
CY2018	cb	Proceeds From Sale Of Available For Sale Securities Debt Condensed ProceedsFromSaleOfAvailableForSaleSecuritiesDebtCondensed	14030000000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	315000000	USD
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CY2018	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	-16000000	USD
CY2018Q3	cb	Net Realized Gains Losses NetRealizedGainsLosses	19000000	USD
CY2019Q4	cb	Net Realized Gains Losses NetRealizedGainsLosses	-55000000	USD
CY2019Q1	us-gaap	Revenues Revenues	7876000000	USD
CY2019Q2	us-gaap	Revenues Revenues	8527000000	USD
CY2019Q3	us-gaap	Revenues Revenues	9045000000	USD
CY2019Q2	us-gaap	Net Investment Income NetInvestmentIncome	859000000	USD
CY2019Q3	us-gaap	Net Investment Income NetInvestmentIncome	873000000	USD
CY2019Q4	us-gaap	Net Investment Income NetInvestmentIncome	858000000	USD
CY2019Q1	cb	Net Realized Gains Losses NetRealizedGainsLosses	-97000000	USD
CY2018	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	1337000000	USD
CY2018	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	980000000	USD
CY2018	cb	Payment Of Contributions To Subsidiary PaymentOfContributionsToSubsidiary	0	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	533000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2935000000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1337000000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1044000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2171000000	USD
CY2018	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	2029000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	2001000000	USD
CY2018	us-gaap	Payments For Securities Purchased Under Agreements To Resell PaymentsForSecuritiesPurchasedUnderAgreementsToResell	2019000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	115000000	USD
CY2018	cb	Advances To From Affiliates Financing Activities AdvancesToFromAffiliatesFinancingActivities	0	USD
CY2018	us-gaap	Cash Dividends Paid To Parent Company CashDividendsPaidToParentCompany	0	USD
CY2018	us-gaap	Proceeds From Contributions From Parent ProceedsFromContributionsFromParent	0	USD
CY2018	us-gaap	Proceeds From Repayments Of Bank Overdrafts ProceedsFromRepaymentsOfBankOverdrafts	0	USD
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CY2018	us-gaap	Withdrawal From Contract Holders Funds WithdrawalFromContractHoldersFunds	358000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1991000000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-65000000	USD
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CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	851000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1340000000	USD
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CY2017	cb	Payments To Acquire Available For Sale Securities Debt Condensed PaymentsToAcquireAvailableForSaleSecuritiesDebtCondensed	25747000000	USD
CY2017	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	352000000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	173000000	USD
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CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	851000000	USD
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CY2017	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	265000000	USD
CY2017	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	648000000	USD
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CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	801000000	USD
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CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	501000000	USD
CY2017	us-gaap	Payments For Securities Purchased Under Agreements To Resell PaymentsForSecuritiesPurchasedUnderAgreementsToResell	2348000000	USD
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CY2017	cb	Advances To From Affiliates Financing Activities AdvancesToFromAffiliatesFinancingActivities	0	USD
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CY2019Q2	cb	Net Realized Gains Losses NetRealizedGainsLosses	-223000000	USD
CY2019Q3	cb	Net Realized Gains Losses NetRealizedGainsLosses	-155000000	USD
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0000896159
CY2019	dei	Entity Registrant Name EntityRegistrantName	Chubb Ltd
CY2017	us-gaap	Cash Acquired From Acquisition CashAcquiredFromAcquisition	0	USD
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CY2019	cb	Deferred Marketing Costs Amortization Period DeferredMarketingCostsAmortizationPeriod	P10Y0M0D
CY2019	dei	Amendment Flag AmendmentFlag	false
CY2019	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	us-gaap	Cash Acquired From Acquisition CashAcquiredFromAcquisition	45000000	USD
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CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	479783864	shares
CY2018Q4	us-gaap	Net Investment Income NetInvestmentIncome	848000000	USD
CY2018Q1	cb	Net Realized Gains Losses NetRealizedGainsLosses	-2000000	USD
CY2018Q2	cb	Net Realized Gains Losses NetRealizedGainsLosses	18000000	USD
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	479783864	shares
CY2017	us-gaap	Concentration Risk Percentage1 ConcentrationRiskPercentage1	0.10
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CY2018	us-gaap	Income Tax Credits And Adjustments IncomeTaxCreditsAndAdjustments	0	USD
CY2018Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	2900000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Before Reclassification Adjustments Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesBeforeReclassificationAdjustmentsTax	228000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Before Reclassification Adjustments Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesBeforeReclassificationAdjustmentsTax	-338000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Before Reclassification Adjustments Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesBeforeReclassificationAdjustmentsTax	647000000	USD
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CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
CY2018Q4	us-gaap	Other Intangible Assets Net OtherIntangibleAssetsNet	6100000000	USD
CY2019	dei	Document Type DocumentType	10-K
CY2019	dei	Document Annual Report DocumentAnnualReport	true
CY2019	dei	Document Period End Date DocumentPeriodEndDate	2019-12-31
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CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	98-0091805
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CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Zurich
CY2019	dei	Entity Address Country EntityAddressCountry	CH
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	8001
CY2019	dei	Country Region CountryRegion	41
CY2019	dei	City Area Code CityAreaCode	(0)43
CY2019	dei	Local Phone Number LocalPhoneNumber	456 76 00
CY2019	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2019	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2019	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2019	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2019	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2019	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2019	dei	Entity Shell Company EntityShellCompany	false
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CY2019Q4	us-gaap	Securities Held As Collateral At Fair Value SecuritiesHeldAsCollateralAtFairValue	994000000	USD
CY2018Q4	us-gaap	Securities Held As Collateral At Fair Value SecuritiesHeldAsCollateralAtFairValue	1926000000	USD
CY2019Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	867000000	USD
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CY2018Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	10075000000	USD
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CY2018Q4	cb	Reinsurance Recoverable Losses And Loss Expenses ReinsuranceRecoverableLossesAndLossExpenses	15993000000	USD
CY2019Q4	cb	Reinsurance Recoverable Future Policy Benefits ReinsuranceRecoverableFuturePolicyBenefits	197000000	USD
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CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	6143000000	USD
CY2019Q4	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	2647000000	USD
CY2018Q4	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	2544000000	USD
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	1332000000	USD
CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	678000000	USD
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CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2018Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	804000000	USD
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CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	3754000000	USD
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CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	29034000000	USD
CY2019	us-gaap	Investment Income Net InvestmentIncomeNet	3426000000	USD
CY2018	us-gaap	Investment Income Net InvestmentIncomeNet	3305000000	USD
CY2017	us-gaap	Investment Income Net InvestmentIncomeNet	3125000000	USD
CY2019	us-gaap	Impairment Of Investments ImpairmentOfInvestments	90000000	USD
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CY2019	cb	Net Realized Gains Losses NetRealizedGainsLosses	-530000000	USD
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CY2017	us-gaap	Revenues Revenues	32243000000	USD
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CY2019	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	740000000	USD
CY2018	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	590000000	USD
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CY2019	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	6153000000	USD
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CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	305000000	USD
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CY2019	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	23000000	USD
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CY2017	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	310000000	USD
CY2019	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	28937000000	USD
CY2018	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	28060000000	USD
CY2017	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	28521000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	5249000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	4657000000	USD
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CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	795000000	USD
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CY2018	us-gaap	Net Income Loss NetIncomeLoss	3962000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	3861000000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	3704000000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-2298000000	USD
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CY2019	us-gaap	Present Value Of Future Insurance Profits Amortization Expense1 PresentValueOfFutureInsuranceProfitsAmortizationExpense1	305000000	USD
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CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	97000000	USD
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CY2019	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	1051000000	USD
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CY2019	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	215000000	USD
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CY2019	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	-302000000	USD
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CY2017	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-517000000	USD
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CY2018	cb	Increase Decrease In Reinsurance Recoverable Losses And Loss Expenses IncreaseDecreaseInReinsuranceRecoverableLossesAndLossExpenses	-1165000000	USD
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CY2019	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	531000000	USD
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CY2017	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	173000000	USD
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CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	13228000000	USD
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CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	611000000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	315000000	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	187000000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	9039000000	USD
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CY2017	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	10425000000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	946000000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1124000000	USD
CY2017	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	879000000	USD
CY2019	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	1117000000	USD
CY2018	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-516000000	USD
CY2017	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	537000000	USD
CY2019	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	703000000	USD
CY2018	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	-16000000	USD
CY2017	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	265000000	USD
CY2019	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	1315000000	USD
CY2018	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	1337000000	USD
CY2017	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	648000000	USD
CY2019	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	1390000000	USD
CY2018	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	980000000	USD
CY2017	us-gaap	Proceeds From Limited Partnership Investments ProceedsFromLimitedPartnershipInvestments	1084000000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	29000000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	1237000000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	533000000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	530000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-5905000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2935000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2422000000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1354000000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1337000000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1308000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-151000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1991000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2319000000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	20000000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1530000000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1044000000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	801000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2828000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2171000000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2019	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	2817000000	USD
CY2018	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	2029000000	USD
CY2017	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	2353000000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	510000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	2001000000	USD
CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	501000000	USD
CY2019	us-gaap	Repayments Of Short Term Debt RepaymentsOfShortTermDebt	2817000000	USD
CY2018	us-gaap	Repayments Of Short Term Debt RepaymentsOfShortTermDebt	2019000000	USD
CY2017	us-gaap	Repayments Of Short Term Debt RepaymentsOfShortTermDebt	2348000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	204000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	115000000	USD
CY2017	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	151000000	USD
CY2019	us-gaap	Additions To Contract Holders Funds AdditionsToContractHoldersFunds	514000000	USD
CY2018	us-gaap	Additions To Contract Holders Funds AdditionsToContractHoldersFunds	453000000	USD
CY2017	us-gaap	Additions To Contract Holders Funds AdditionsToContractHoldersFunds	442000000	USD
CY2019	us-gaap	Withdrawal From Contract Holders Funds WithdrawalFromContractHoldersFunds	303000000	USD
CY2018	us-gaap	Withdrawal From Contract Holders Funds WithdrawalFromContractHoldersFunds	358000000	USD
CY2017	us-gaap	Withdrawal From Contract Holders Funds WithdrawalFromContractHoldersFunds	307000000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-65000000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	1000000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	306000000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	489000000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-237000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1340000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	851000000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1088000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1646000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1340000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	851000000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	912000000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	503000000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	736000000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	512000000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	621000000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	644000000	USD
CY2019Q4	us-gaap	Deferred Advertising Costs DeferredAdvertisingCosts	246000000	USD
CY2018Q4	us-gaap	Deferred Advertising Costs DeferredAdvertisingCosts	255000000	USD
CY2019	cb	Recoverable From Unrated Reinsurers Ceded Reserve Default Factor RecoverableFromUnratedReinsurersCededReserveDefaultFactor	0.34
CY2019	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	6000000	USD
CY2018	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	14000000	USD
CY2019	cb	Borrowers Collateral Percent Of Fair Value Loaned Securities BorrowersCollateralPercentOfFairValueLoanedSecurities	1.02
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1537000000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1247000000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	728000000	USD
CY2019Q4	us-gaap	Restricted Cash RestrictedCash	109000000	USD
CY2018Q4	us-gaap	Restricted Cash RestrictedCash	93000000	USD
CY2017Q4	us-gaap	Restricted Cash RestrictedCash	123000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1646000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1340000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	851000000	USD
CY2019	cb	Goodwill Impairment Testing Qualitative Assessment Percentage Probability GoodwillImpairmentTestingQualitativeAssessmentPercentageProbability	0.50
CY2019	cb	Goodwill Impairment Testing Qualitative Assessment Percentage Probability GoodwillImpairmentTestingQualitativeAssessmentPercentageProbability	0.50
CY2019Q4	us-gaap	Deposit Assets DepositAssets	93000000	USD
CY2018Q4	us-gaap	Deposit Assets DepositAssets	97000000	USD
CY2019Q4	us-gaap	Deposit Contracts Liabilities DepositContractsLiabilities	88000000	USD
CY2018Q4	us-gaap	Deposit Contracts Liabilities DepositContractsLiabilities	97000000	USD
CY2019Q4	us-gaap	Borrowings Under Guaranteed Investment Agreements BorrowingsUnderGuaranteedInvestmentAgreements	2000000000.0	USD
CY2018Q4	us-gaap	Borrowings Under Guaranteed Investment Agreements BorrowingsUnderGuaranteedInvestmentAgreements	1800000000	USD
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CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1700000000	USD
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CY2018	cb	Net Operating Results Of Esis Included Within Administrative Expenses NetOperatingResultsOfEsisIncludedWithinAdministrativeExpenses	49000000	USD
CY2017	cb	Net Operating Results Of Esis Included Within Administrative Expenses NetOperatingResultsOfEsisIncludedWithinAdministrativeExpenses	38000000	USD
CY2019	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	23000000	USD
CY2018	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	59000000	USD
CY2017	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	310000000	USD
CY2019	us-gaap	Description Of New Accounting Pronouncements Not Yet Adopted DescriptionOfNewAccountingPronouncementsNotYetAdopted	<div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;font-style:italic;font-weight:bold;">Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Instruments</span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Effective January 1, 2020, we adopted, on a modified retrospective basis, new guidance on the accounting for credit losses of financial instruments that are measured at amortized cost, including held to maturity securities, reinsurance recoverables, and high deductible receivables, by applying an approach based on the current expected credit losses (CECL). The estimate of </span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">expected credit losses considers historical information, current information, as well as reasonable and supportable forecasts, including estimates of prepayments. In addition, the guidance also amended the current available for sale (AFS) debt security other-than-temporary impairment model by requiring an estimate of the expected credit loss (ECL) only when the fair value is below the amortized cost of the asset. The length of time the fair value of an AFS security has been below the amortized cost no longer impacts the determination of whether a potential credit loss exists. The AFS security model also requires the use of a valuation allowance as compared to the current practice of writing down the asset. </span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"><br/></span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">During the first quarter of 2020, we established a valuation allowance for credit losses and recognized a cumulative effect adjustment and decreased beginning retained earnings by approximately </span><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"><span>$70 million</span></span><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"> pre-tax, or </span><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"><span>$64 million</span></span><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"> after-tax.</span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"><br/></span></div><div style="line-height:120%;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;font-weight:bold;">Accounting guidance not yet adopted</span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;font-style:italic;font-weight:bold;">Targeted Improvements to the Accounting for Long-Duration Contracts</span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">In August 2018, the FASB issued guidance to improve the existing recognition, measurement, presentation, and disclosure requirements for long-duration contracts issued by an insurance entity. The amendments in this update require more frequent updating of assumptions and a standardized discount rate for the future policy benefit liability, a requirement to use the fair value measurement model for policies with market risk benefits, simplified amortization of deferred acquisition costs, and enhanced disclosures. This standard will be effective for us in the first quarter of 2022 with early adoption permitted. We are currently assessing the effect of adopting this guidance on our financial condition and results of operations. We will be better able to quantify the effect of adopting this standard as we progress in our implementation process and draw nearer to the date of adoption.</span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"><br/></span></div><div style="line-height:120%;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;font-style:italic;font-weight:bold;">Income Taxes - Simplifying the Accounting for Income Taxes</span></div>In December 2019, the FASB issued updated guidance for the accounting for income taxes. The updated guidance is intended to simplify the accounting for income taxes by removing several exceptions contained in existing guidance and amending other existing guidance to simplify several other income tax accounting matters. The updated guidance is effective for us in the first quarter of 2021 with early adoption permitted. We are currently evaluating the impact of this guidance on our financial condition and results of operations; however, it is not expected to have a material impact at the date of adoption.
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	82580000000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	3074000000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	166000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	85488000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Availableforsale Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxAvailableforsaleDebtSecurities	30000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	12581000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	427000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	3000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	13005000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Heldtomaturity Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxHeldtomaturityDebtSecurities	0	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	79323000000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	690000000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1543000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	78470000000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Availableforsale Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxAvailableforsaleDebtSecurities	7000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	13435000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	51000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	227000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	13259000000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Heldtomaturity Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxHeldtomaturityDebtSecurities	0	USD
CY2019	cb	Net Unrealized Appreciation Included In Other Comprehensive Income NetUnrealizedAppreciationIncludedInOtherComprehensiveIncome	3000000	USD
CY2018	cb	Net Unrealized Appreciation Included In Other Comprehensive Income NetUnrealizedAppreciationIncludedInOtherComprehensiveIncome	-4000000	USD
CY2019Q4	cb	Aoci Portion Attributabletochangeof F Vofinvestmentswith Otti AOCIPortionAttributabletochangeofFVofinvestmentswithOTTI	18000000	USD
CY2018Q4	cb	Aoci Portion Attributabletochangeof F Vofinvestmentswith Otti AOCIPortionAttributabletochangeofFVofinvestmentswithOTTI	-1000000	USD
CY2019Q4	cb	Mortgage Backed Securities Percentage United States Government Agency Bonds MortgageBackedSecuritiesPercentageUnitedStatesGovernmentAgencyBonds	0.83
CY2018Q4	cb	Mortgage Backed Securities Percentage United States Government Agency Bonds MortgageBackedSecuritiesPercentageUnitedStatesGovernmentAgencyBonds	0.81
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	3951000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	3973000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	3569000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	3568000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	27142000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	27720000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	27134000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	27005000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	23901000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	24874000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	24095000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	23543000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	8874000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	9729000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	8767000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	8814000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	63868000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	66296000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	63565000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	62930000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	18712000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	19192000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	15758000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	15540000000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	82580000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	85488000000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	79323000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	78470000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	478000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	479000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	536000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	537000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	3869000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	3940000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	3122000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	3106000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	3756000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	3883000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	4468000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	4407000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	2147000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	2307000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	2785000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	2723000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	10250000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	10609000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	10911000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	10773000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	2331000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	2396000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	2524000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	2486000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	12581000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	13005000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	13435000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	13259000000	USD
CY2019Q4	cb	Fixed Maturities In Unrealized Loss Position Number FixedMaturitiesInUnrealizedLossPositionNumber	4091	Security
CY2019Q4	cb	Fixed Maturities Total Number FixedMaturitiesTotalNumber	31203	Security
CY2019Q4	cb	Fixed Maturities Largest Single Unrealized Loss FixedMaturitiesLargestSingleUnrealizedLoss	6000000	USD
CY2019Q4	cb	Portion Of Gross Unrealized Loss Represented By United States Treasury And Agency Obligations PortionOfGrossUnrealizedLossRepresentedByUnitedStatesTreasuryAndAgencyObligations	61000000	USD
CY2019	cb	Moodys Historical Mean Recovery Rate MoodysHistoricalMeanRecoveryRate	0.42
CY2018Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	34000000	USD
CY2017Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	22000000	USD
CY2016Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	35000000	USD
CY2019	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	33000000	USD
CY2018	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	20000000	USD
CY2017	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	4000000	USD
CY2019	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	4000000	USD
CY2018	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	5000000	USD
CY2017	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	2000000	USD
CY2019	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	41000000	USD
CY2018	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	13000000	USD
CY2017	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	19000000	USD
CY2019Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	30000000	USD
CY2018Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	34000000	USD
CY2017Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	22000000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	7000000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	131000000	USD
CY2017	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	36000000	USD
CY2019	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	-4000000	USD
CY2018	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	-248000000	USD
CY2017	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	364000000	USD
CY2019	cb	Net Realized Gains Losses NetRealizedGainsLosses	-530000000	USD
CY2018	cb	Net Realized Gains Losses NetRealizedGainsLosses	-652000000	USD
CY2017	cb	Net Realized Gains Losses NetRealizedGainsLosses	84000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	647000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-297000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	241000000	USD
CY2019	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	3088000000	USD
CY2018	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-1699000000	USD
CY2017	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	392000000	USD
CY2019Q4	us-gaap	Alternative Investment AlternativeInvestment	4921000000	USD
CY2019Q4	us-gaap	Fair Value Investments Entities That Calculate Net Asset Value Per Share Unfunded Committments FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments	3263000000	USD
CY2018Q4	us-gaap	Alternative Investment AlternativeInvestment	4244000000	USD
CY2018Q4	us-gaap	Fair Value Investments Entities That Calculate Net Asset Value Per Share Unfunded Committments FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments	3705000000	USD
CY2019	cb	Limited Partnerships Number LimitedPartnershipsNumber	131	partnerships
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	1332000000	USD
CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	678000000	USD
CY2019	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	3598000000	USD
CY2018	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	3473000000	USD
CY2017	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	3289000000	USD
CY2019	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	172000000	USD
CY2018	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	168000000	USD
CY2017	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	164000000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	3426000000	USD
CY2018	us-gaap	Net Investment Income NetInvestmentIncome	3305000000	USD
CY2017	us-gaap	Net Investment Income NetInvestmentIncome	3125000000	USD
CY2019Q4	us-gaap	Restricted Investments RestrictedInvestments	21000000000.0	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	109000000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	93000000	USD
CY2019Q4	us-gaap	Funds Held Under Reinsurance Agreements Asset FundsHeldUnderReinsuranceAgreementsAsset	14004000000	USD
CY2018Q4	us-gaap	Funds Held Under Reinsurance Agreements Asset FundsHeldUnderReinsuranceAgreementsAsset	13988000000	USD
CY2019Q4	cb	Restricted Assets Deposits With United States Regulatory Authorities RestrictedAssetsDepositsWithUnitedStatesRegulatoryAuthorities	2466000000	USD
CY2018Q4	cb	Restricted Assets Deposits With United States Regulatory Authorities RestrictedAssetsDepositsWithUnitedStatesRegulatoryAuthorities	2405000000	USD
CY2019Q4	cb	Restricted Assets Deposits With Non United States Regulatory Authorities RestrictedAssetsDepositsWithNonUnitedStatesRegulatoryAuthorities	2709000000	USD
CY2018Q4	cb	Restricted Assets Deposits With Non United States Regulatory Authorities RestrictedAssetsDepositsWithNonUnitedStatesRegulatoryAuthorities	2531000000	USD
CY2019Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities For Repurchase Agreements PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForRepurchaseAgreements	1464000000	USD
CY2018Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities For Repurchase Agreements PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForRepurchaseAgreements	1468000000	USD
CY2019Q4	cb	Restricted Assets Other Pledged Assets RestrictedAssetsOtherPledgedAssets	490000000	USD
CY2018Q4	cb	Restricted Assets Other Pledged Assets RestrictedAssetsOtherPledgedAssets	692000000	USD
CY2019Q4	us-gaap	Restricted Cash And Investments RestrictedCashAndInvestments	21133000000	USD
CY2018Q4	us-gaap	Restricted Cash And Investments RestrictedCashAndInvestments	21084000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	13005000000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	13259000000	USD
CY2019	us-gaap	Direct Premiums Written DirectPremiumsWritten	36848000000	USD
CY2018	us-gaap	Direct Premiums Written DirectPremiumsWritten	34782000000	USD
CY2017	us-gaap	Direct Premiums Written DirectPremiumsWritten	33137000000	USD
CY2019	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	3276000000	USD
CY2018	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	3186000000	USD
CY2017	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	3239000000	USD
CY2019	us-gaap	Ceded Premiums Written CededPremiumsWritten	7849000000	USD
CY2018	us-gaap	Ceded Premiums Written CededPremiumsWritten	7389000000	USD
CY2017	us-gaap	Ceded Premiums Written CededPremiumsWritten	7132000000	USD
CY2019	us-gaap	Premiums Written Net PremiumsWrittenNet	32275000000	USD
CY2018	us-gaap	Premiums Written Net PremiumsWrittenNet	30579000000	USD
CY2017	us-gaap	Premiums Written Net PremiumsWrittenNet	29244000000	USD
CY2019	us-gaap	Direct Premiums Earned DirectPremiumsEarned	35876000000	USD
CY2018	us-gaap	Direct Premiums Earned DirectPremiumsEarned	34108000000	USD
CY2017	us-gaap	Direct Premiums Earned DirectPremiumsEarned	32782000000	USD
CY2019	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	3107000000	USD
CY2018	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	3175000000	USD
CY2017	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	3332000000	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	7693000000	USD
CY2018	us-gaap	Ceded Premiums Earned CededPremiumsEarned	7219000000	USD
CY2017	us-gaap	Ceded Premiums Earned CededPremiumsEarned	7080000000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	31290000000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	30064000000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	29034000000	USD
CY2019	cb	Reinsurance Recoveries Losses And Loss Expenses Incurred ReinsuranceRecoveriesLossesAndLossExpensesIncurred	4900000000	USD
CY2018	cb	Reinsurance Recoveries Losses And Loss Expenses Incurred ReinsuranceRecoveriesLossesAndLossExpensesIncurred	5600000000	USD
CY2017	cb	Reinsurance Recoveries Losses And Loss Expenses Incurred ReinsuranceRecoveriesLossesAndLossExpensesIncurred	5500000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	14181000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Allowance ReinsuranceRecoverablesOnUnpaidLossesAllowance	240000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	14689000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Allowance ReinsuranceRecoverablesOnUnpaidLossesAllowance	251000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables On Paid Losses ReinsuranceRecoverablesOnPaidLosses	1000000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables On Paid Losses Allowance ReinsuranceRecoverablesOnPaidLossesAllowance	76000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverables On Paid Losses ReinsuranceRecoverablesOnPaidLosses	1304000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverables On Paid Losses Allowance ReinsuranceRecoverablesOnPaidLossesAllowance	72000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	15181000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	316000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	15993000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	323000000	USD
CY2019Q4	cb	Reinsurance Recoverable Future Policy Benefits ReinsuranceRecoverableFuturePolicyBenefits	197000000	USD
CY2019Q4	cb	Reinsurance Recoverableson Future Policy Benefits Allowance ReinsuranceRecoverablesonFuturePolicyBenefitsAllowance	4000000	USD
CY2018Q4	cb	Reinsurance Recoverable Future Policy Benefits ReinsuranceRecoverableFuturePolicyBenefits	202000000	USD
CY2018Q4	cb	Reinsurance Recoverableson Future Policy Benefits Allowance ReinsuranceRecoverablesonFuturePolicyBenefitsAllowance	4000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	15497000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	316000000	USD
CY2019Q4	cb	Allowance For Reinsurance Recoverable Percentage AllowanceForReinsuranceRecoverablePercentage	0.020
CY2019	us-gaap	Net Amount At Risk By Product And Guarantee Weighted Average Attained Age1 NetAmountAtRiskByProductAndGuaranteeWeightedAverageAttainedAge1	P72Y
CY2019Q4	us-gaap	Goodwill Goodwill	15300000000	USD
CY2019Q4	us-gaap	Other Intangible Assets Net OtherIntangibleAssetsNet	6100000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	3200000000	USD
CY2019Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	2900000000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	15541000000	USD
CY2018	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-270000000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	15271000000	USD
CY2019	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	25000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	15296000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	305000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	339000000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	260000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	290000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	280000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	275000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	261000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	239000000	USD
CY2019Q4	cb	Finitelivedintangibleassetsamortizationexpensetotal Finitelivedintangibleassetsamortizationexpensetotal	1345000000	USD
CY2018Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	295000000	USD
CY2017Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	326000000	USD
CY2016Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	355000000	USD
CY2019	us-gaap	Present Value Of Future Insurance Profits Additions From Acquisitions PresentValueOfFutureInsuranceProfitsAdditionsFromAcquisitions	35000000	USD
CY2018	us-gaap	Present Value Of Future Insurance Profits Additions From Acquisitions PresentValueOfFutureInsuranceProfitsAdditionsFromAcquisitions	0	USD
CY2017	us-gaap	Present Value Of Future Insurance Profits Additions From Acquisitions PresentValueOfFutureInsuranceProfitsAdditionsFromAcquisitions	0	USD
CY2019	us-gaap	Amortization Of Value Of Business Acquired Voba AmortizationOfValueOfBusinessAcquiredVOBA	24000000	USD
CY2018	us-gaap	Amortization Of Value Of Business Acquired Voba AmortizationOfValueOfBusinessAcquiredVOBA	25000000	USD
CY2017	us-gaap	Amortization Of Value Of Business Acquired Voba AmortizationOfValueOfBusinessAcquiredVOBA	35000000	USD
CY2019	cb	Intangible Assets Arising From Insurance Contracts Acquired In Business Combination Foreign Exchange Revaluation IntangibleAssetsArisingFromInsuranceContractsAcquiredInBusinessCombinationForeignExchangeRevaluation	0	USD
CY2018	cb	Intangible Assets Arising From Insurance Contracts Acquired In Business Combination Foreign Exchange Revaluation IntangibleAssetsArisingFromInsuranceContractsAcquiredInBusinessCombinationForeignExchangeRevaluation	-6000000	USD
CY2017	cb	Intangible Assets Arising From Insurance Contracts Acquired In Business Combination Foreign Exchange Revaluation IntangibleAssetsArisingFromInsuranceContractsAcquiredInBusinessCombinationForeignExchangeRevaluation	6000000	USD
CY2019Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	306000000	USD
CY2018Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	295000000	USD
CY2017Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	326000000	USD
CY2019Q4	us-gaap	Present Value Of Future Insurance Profits Amortization Expense Year One PresentValueOfFutureInsuranceProfitsAmortizationExpenseYearOne	26000000	USD
CY2019Q4	us-gaap	Present Value Of Future Insurance Profits Amortization Expense Year Two PresentValueOfFutureInsuranceProfitsAmortizationExpenseYearTwo	24000000	USD
CY2019Q4	us-gaap	Present Value Of Future Insurance Profits Amortization Expense Year Three PresentValueOfFutureInsuranceProfitsAmortizationExpenseYearThree	22000000	USD
CY2019Q4	us-gaap	Present Value Of Future Insurance Profits Amortization Expense Year Four PresentValueOfFutureInsuranceProfitsAmortizationExpenseYearFour	21000000	USD
CY2019Q4	us-gaap	Present Value Of Future Insurance Profits Amortization Expense Year Five PresentValueOfFutureInsuranceProfitsAmortizationExpenseYearFive	19000000	USD
CY2019Q4	us-gaap	Present Value Of Future Insurance Profits Accumulated Amortization PresentValueOfFutureInsuranceProfitsAccumulatedAmortization	112000000	USD
CY2019	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="line-height:120%;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"><br/></span></div><div style="line-height:120%;padding-bottom:9px;text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Chubb establishes reserves for the estimated unpaid ultimate liability for losses and loss expenses under the terms of its policies and agreements. Reserves include estimates for both claims that have been reported and for IBNR claims, and include estimates of expenses associated with processing and settling these claims. Reserves are recorded in Unpaid losses and loss expenses in the consolidated balance sheets. While we believe that our reserves for unpaid losses and loss expenses at </span><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">December 31, 2019</span><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;"> are adequate, new information or trends may lead to future developments in incurred loss and loss expenses significantly greater or less than the reserves provided. Any such revisions could result in future changes in estimates of losses or reinsurance recoverable and would be reflected in our results of operations in the period in which the estimates are changed.</span></div><div style="line-height:120%;font-size:10pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">The following table presents a reconciliation of </span><span style="font-family:News Gothic,sans-serif;font-size:10pt;">beginning and ending </span><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Unpaid losses and loss expenses:</span></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="12"/></tr><tr><td style="width:65%;"/><td style="width:1%;"/><td style="width:9%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:9%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:9%;"/><td style="width:1%;"/></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="10" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">Year Ended December 31</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">(in millions of U.S. dollars)</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;">2019</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">2018</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">2017</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Gross unpaid losses and loss expenses, beginning of year</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>62,960</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>63,179</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>60,540</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Reinsurance recoverable on unpaid losses </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><sup style="vertical-align:top;line-height:120%;font-size:pt">(1)</sup></span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>(14,689</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;">)</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>(14,014</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">)</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>(12,708</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">)</span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Net unpaid losses and loss expenses, beginning of year</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>48,271</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>49,165</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>47,832</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Net losses and loss expenses incurred in respect of losses occurring in:</span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Current year</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>19,575</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>19,048</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>19,391</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Prior years </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><sup style="vertical-align:top;line-height:120%;font-size:pt">(2)</sup></span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>(845</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;">)</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>(981</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">)</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>(937</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">)</span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Total</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>18,730</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>18,067</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>18,454</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Net losses and loss expenses paid in respect of losses occurring in:</span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Current year</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>7,894</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>7,544</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>6,575</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Prior years</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>10,579</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>10,796</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>10,873</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Total</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>18,473</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>18,340</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>17,448</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Foreign currency revaluation and other</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>(19</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-right:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;">)</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>(621</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-right:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">)</span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>327</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Net unpaid losses and loss expenses, end of year</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>48,509</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>48,271</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>49,165</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Reinsurance recoverable on unpaid losses </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><sup style="vertical-align:top;line-height:120%;font-size:pt">(1)</sup></span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>14,181</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>14,689</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>14,014</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9.75pt;"><span style="font-family:News Gothic,sans-serif;font-size:9.75pt;">Gross unpaid losses and loss expenses, end of year</span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;">$</span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;font-weight:bold;"><span>62,690</span></span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>62,960</span></span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:8.5pt;"><span style="font-family:News Gothic,sans-serif;font-size:8.5pt;"><span>63,179</span></span></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr></table></div></div><table cellpadding="0" cellspacing="0" style="padding-top:4px;font-family:Times New Roman; font-size:10pt;"><tr><td style="width:24px;"/><td/></tr><tr><td style="vertical-align:top"><div style="line-height:120%;font-size:7pt;padding-left:0px;"><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><sup style="vertical-align:top;line-height:120%;font-size:pt">(1)</sup></span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"> </span></div></td><td style="vertical-align:top;"><div style="line-height:120%;font-size:7pt;"><span style="font-family:News Gothic,sans-serif;font-size:7pt;">Net of provision for uncollectible reinsurance.</span></div></td></tr></table><table cellpadding="0" cellspacing="0" style="padding-top:4px;font-family:Times New Roman; font-size:10pt;"><tr><td style="width:24px;"/><td/></tr><tr><td style="vertical-align:top"><div style="line-height:120%;font-size:7pt;padding-left:0px;"><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><sup style="vertical-align:top;line-height:120%;font-size:pt">(2)</sup> </span></div></td><td style="vertical-align:top;"><div style="line-height:120%;font-size:7pt;"><span style="font-family:News Gothic,sans-serif;font-size:7pt;">Relates to prior period loss reserve development only and excludes prior period development related to reinstatement premiums, expense adjustments and earned premiums totaling </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><span>$53 million</span></span><span style="font-family:News Gothic,sans-serif;font-size:7pt;">, </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><span>$85 million</span></span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"> and </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"><span>$108 million</span></span><span style="font-family:News Gothic,sans-serif;font-size:7pt;"> for </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;">2019</span><span style="font-family:News Gothic,sans-serif;font-size:7pt;">, </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;">2018</span><span style="font-family:News Gothic,sans-serif;font-size:7pt;">, and </span><span style="font-family:News Gothic,sans-serif;font-size:7pt;">2017</span><span style="font-family:News Gothic,sans-serif;font-size:7pt;">, respectively. </span></div></td></tr></table><div style="line-height:120%;text-align:left;font-size:9pt;"><span style="font-family:News Gothic,sans-serif;font-size:9pt;"><br/></span></div>
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	62960000000	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	63179000000	USD
CY2016Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	60540000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	14689000000	USD
CY2017Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	14014000000	USD
CY2016Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	12708000000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	48271000000	USD
CY2017Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	49165000000	USD
CY2016Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	47832000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	19575000000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	19048000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	19391000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-845000000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-981000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-937000000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	18730000000	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	18067000000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	18454000000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	7894000000	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	7544000000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	6575000000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	10579000000	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	10796000000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	10873000000	USD
CY2019	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	18473000000	USD
CY2018	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	18340000000	USD
CY2017	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	17448000000	USD
CY2019Q4	cb	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Revaluation And Other LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyRevaluationAndOther	-19000000	USD
CY2018Q4	cb	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Revaluation And Other LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyRevaluationAndOther	-621000000	USD
CY2017Q4	cb	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Revaluation And Other LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyRevaluationAndOther	327000000	USD
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	48509000000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	48271000000	USD
CY2017Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	49165000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	14181000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	14689000000	USD
CY2017Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	14014000000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	62690000000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	62960000000	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	63179000000	USD
CY2019	cb	Prior Period Developmentnetadjustments PriorPeriodDevelopmentnetadjustments	53000000	USD
CY2018	cb	Prior Period Developmentnetadjustments PriorPeriodDevelopmentnetadjustments	85000000	USD
CY2017	cb	Prior Period Developmentnetadjustments PriorPeriodDevelopmentnetadjustments	108000000	USD
CY2019Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet	46062000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	14331000000	USD
CY2019Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claim Adjustment Expense Aggregate Reconciling Items ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimAdjustmentExpenseAggregateReconcilingItems	873000000	USD
CY2019Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claims Adjustment Expense Accumulated Unallocated Claim Adjustment Expense ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAccumulatedUnallocatedClaimAdjustmentExpense	1424000000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	62690000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-845000000	USD
CY2019	cb	Prior Period Developmentnetadjustments PriorPeriodDevelopmentnetadjustments	53000000	USD
CY2019	cb	Net Prior Period Development NetPriorPeriodDevelopment	-792000000	USD
CY2019	cb	Net Prior Period Development NetPriorPeriodDevelopment	-792000000	USD
CY2019Q4	cb	Prior Period Development Percentage Opening Net Unpaid Reserves PriorPeriodDevelopmentPercentageOpeningNetUnpaidReserves	0.016
CY2018	cb	Net Prior Period Development NetPriorPeriodDevelopment	-896000000	USD
CY2018Q4	cb	Prior Period Development Percentage Opening Net Unpaid Reserves PriorPeriodDevelopmentPercentageOpeningNetUnpaidReserves	0.018
CY2017	cb	Net Prior Period Development NetPriorPeriodDevelopment	-829000000	USD
CY2017Q4	cb	Prior Period Development Percentage Opening Net Unpaid Reserves PriorPeriodDevelopmentPercentageOpeningNetUnpaidReserves	0.017
CY2016Q4	us-gaap	Liability For Asbestos And Environmental Claims Gross LiabilityForAsbestosAndEnvironmentalClaimsGross	2303000000	USD
CY2016Q4	us-gaap	Liability For Asbestos And Environmental Claims Net LiabilityForAsbestosAndEnvironmentalClaimsNet	1609000000	USD
CY2017	us-gaap	Liability For Asbestos And Environmental Claims Gross Incurred Loss1 LiabilityForAsbestosAndEnvironmentalClaimsGrossIncurredLoss1	427000000	USD
CY2017	us-gaap	Liability For Asbestos And Environmental Claims Net Incurred Loss1 LiabilityForAsbestosAndEnvironmentalClaimsNetIncurredLoss1	217000000	USD
CY2017	us-gaap	Liability For Asbestos And Environmental Claims Gross Payment For Claims LiabilityForAsbestosAndEnvironmentalClaimsGrossPaymentForClaims	502000000	USD
CY2017	us-gaap	Liability For Asbestos And Environmental Claims Net Payment For Claims LiabilityForAsbestosAndEnvironmentalClaimsNetPaymentForClaims	299000000	USD
CY2017Q4	us-gaap	Liability For Asbestos And Environmental Claims Gross LiabilityForAsbestosAndEnvironmentalClaimsGross	2228000000	USD
CY2017Q4	us-gaap	Liability For Asbestos And Environmental Claims Net LiabilityForAsbestosAndEnvironmentalClaimsNet	1527000000	USD
CY2018	us-gaap	Liability For Asbestos And Environmental Claims Gross Incurred Loss1 LiabilityForAsbestosAndEnvironmentalClaimsGrossIncurredLoss1	237000000	USD
CY2018	us-gaap	Liability For Asbestos And Environmental Claims Net Incurred Loss1 LiabilityForAsbestosAndEnvironmentalClaimsNetIncurredLoss1	-22000000	USD
CY2018	us-gaap	Liability For Asbestos And Environmental Claims Gross Payment For Claims LiabilityForAsbestosAndEnvironmentalClaimsGrossPaymentForClaims	348000000	USD
CY2018	us-gaap	Liability For Asbestos And Environmental Claims Net Payment For Claims LiabilityForAsbestosAndEnvironmentalClaimsNetPaymentForClaims	58000000	USD
CY2018Q4	us-gaap	Liability For Asbestos And Environmental Claims Gross LiabilityForAsbestosAndEnvironmentalClaimsGross	2117000000	USD
CY2018Q4	us-gaap	Liability For Asbestos And Environmental Claims Net LiabilityForAsbestosAndEnvironmentalClaimsNet	1447000000	USD
CY2019	us-gaap	Liability For Asbestos And Environmental Claims Gross Incurred Loss1 LiabilityForAsbestosAndEnvironmentalClaimsGrossIncurredLoss1	175000000	USD
CY2019	us-gaap	Liability For Asbestos And Environmental Claims Net Incurred Loss1 LiabilityForAsbestosAndEnvironmentalClaimsNetIncurredLoss1	98000000	USD
CY2019	us-gaap	Liability For Asbestos And Environmental Claims Gross Payment For Claims LiabilityForAsbestosAndEnvironmentalClaimsGrossPaymentForClaims	304000000	USD
CY2019	us-gaap	Liability For Asbestos And Environmental Claims Net Payment For Claims LiabilityForAsbestosAndEnvironmentalClaimsNetPaymentForClaims	219000000	USD
CY2019Q4	us-gaap	Liability For Asbestos And Environmental Claims Gross LiabilityForAsbestosAndEnvironmentalClaimsGross	1988000000	USD
CY2019Q4	us-gaap	Liability For Asbestos And Environmental Claims Net LiabilityForAsbestosAndEnvironmentalClaimsNet	1326000000	USD
CY2019Q4	us-gaap	Liability For Asbestos And Environmental Claims Net LiabilityForAsbestosAndEnvironmentalClaimsNet	1326000000	USD
CY2018Q4	us-gaap	Liability For Asbestos And Environmental Claims Net LiabilityForAsbestosAndEnvironmentalClaimsNet	1447000000	USD
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	291000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	440000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	950000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	527000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	4809000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	3707000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	3195000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	5249000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	4657000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	3722000000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	908000000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	652000000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	359000000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-113000000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	43000000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-498000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	795000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	695000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-139000000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	411000000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	365000000	USD
CY2019	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	376000000	USD
CY2018	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	372000000	USD
CY2017	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	263000000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	49000000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	75000000	USD
CY2017	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	199000000	USD
CY2019	cb	Income Tax Reconciliation Net Witholding Taxes IncomeTaxReconciliationNetWitholdingTaxes	40000000	USD
CY2018	cb	Income Tax Reconciliation Net Witholding Taxes IncomeTaxReconciliationNetWitholdingTaxes	33000000	USD
CY2017	cb	Income Tax Reconciliation Net Witholding Taxes IncomeTaxReconciliationNetWitholdingTaxes	30000000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-12000000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-19000000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-48000000	USD
CY2019	cb	Incometaxbenefitrelatedto2017 Tax Act Incometaxbenefitrelatedto2017TaxAct	0	USD
CY2018	cb	Incometaxbenefitrelatedto2017 Tax Act Incometaxbenefitrelatedto2017TaxAct	-25000000	USD
CY2017	cb	Incometaxbenefitrelatedto2017 Tax Act Incometaxbenefitrelatedto2017TaxAct	-450000000	USD
CY2019	cb	Income Tax Reconciliation Corporate Owned Life Insurance IncomeTaxReconciliationCorporateOwnedLifeInsurance	-13000000	USD
CY2018	cb	Income Tax Reconciliation Corporate Owned Life Insurance IncomeTaxReconciliationCorporateOwnedLifeInsurance	2000000	USD
CY2017	cb	Income Tax Reconciliation Corporate Owned Life Insurance IncomeTaxReconciliationCorporateOwnedLifeInsurance	-37000000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	42000000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	42000000	USD
CY2017	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	11000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	795000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	695000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-139000000	USD
CY2018	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	475000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	826000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	584000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	519000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	471000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	247000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	262000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	37000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	37000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Capital Loss Carryforwards DeferredTaxAssetsCapitalLossCarryforwards	143000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Capital Loss Carryforwards DeferredTaxAssetsCapitalLossCarryforwards	137000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	74000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	71000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	261000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	263000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Unrealized Currency Losses DeferredTaxAssetsUnrealizedCurrencyLosses	33000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Unrealized Currency Losses DeferredTaxAssetsUnrealizedCurrencyLosses	43000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Trading Securities DeferredTaxAssetsUnrealizedLossesOnTradingSecurities	0	USD
CY2018Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Trading Securities DeferredTaxAssetsUnrealizedLossesOnTradingSecurities	102000000	USD
CY2019Q4	cb	Deferred Tax Asset Lease Liability DeferredTaxAssetLeaseLiability	140000000	USD
CY2018Q4	cb	Deferred Tax Asset Lease Liability DeferredTaxAssetLeaseLiability	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	0	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	95000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	2280000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	2065000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	588000000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	621000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	1468000000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	1440000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	73000000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Undistributed Foreign Earnings DeferredTaxLiabilitiesUndistributedForeignEarnings	47000000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	0	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	40000000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	59000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	470000000	USD
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CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	47000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	14000000	USD
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CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	75000000	USD
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CY2018Q4	us-gaap	Securities Held As Collateral At Fair Value SecuritiesHeldAsCollateralAtFairValue	1926000000	USD
CY2019Q4	us-gaap	Obligation To Return Securities Received As Collateral ObligationToReturnSecuritiesReceivedAsCollateral	994000000	USD
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CY2018Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	1418000000	USD
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CY2019	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	321800	shares
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CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	617000000	USD
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CY2017	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	35000000	USD
CY2019	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	42000000	USD
CY2018	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	30000000	USD
CY2017	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	30000000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	596000000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	434000000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	400000000	USD
CY2019	us-gaap	Premiums Written Net PremiumsWrittenNet	32275000000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	31290000000	USD
CY2019	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	18730000000	USD
CY2019	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	740000000	USD
CY2019	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	6153000000	USD
CY2019	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	3030000000	USD
CY2019	cb	Underwriting Income Loss Insurance UnderwritingIncomeLossInsurance	2637000000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	3426000000	USD
CY2019	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	596000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	305000000	USD
CY2019	cb	Segment Underwriting Income Lossand Net Investment Income Loss SegmentUnderwritingIncomeLossandNetInvestmentIncomeLoss	6354000000	USD
CY2019	cb	Net Realized Gains Losses NetRealizedGainsLosses	-530000000	USD
CY2019	us-gaap	Interest Expense InterestExpense	552000000	USD
CY2019	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	23000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	795000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4454000000	USD
CY2018	us-gaap	Premiums Written Net PremiumsWrittenNet	30579000000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	30064000000	USD
CY2018	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	18067000000	USD
CY2018	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	590000000	USD
CY2018	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	5912000000	USD
CY2018	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	2886000000	USD
CY2018	cb	Underwriting Income Loss Insurance UnderwritingIncomeLossInsurance	2609000000	USD
CY2018	us-gaap	Net Investment Income NetInvestmentIncome	3305000000	USD
CY2018	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	434000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	339000000	USD
CY2018	cb	Segment Underwriting Income Lossand Net Investment Income Loss SegmentUnderwritingIncomeLossandNetInvestmentIncomeLoss	6009000000	USD
CY2018	cb	Net Realized Gains Losses NetRealizedGainsLosses	-652000000	USD
CY2018	us-gaap	Interest Expense InterestExpense	641000000	USD
CY2018	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	59000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	695000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	3962000000	USD
CY2017	us-gaap	Premiums Written Net PremiumsWrittenNet	29244000000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	29034000000	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	18454000000	USD
CY2017	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	676000000	USD
CY2017	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	5781000000	USD
CY2017	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	2833000000	USD
CY2017	cb	Underwriting Income Loss Insurance UnderwritingIncomeLossInsurance	1290000000	USD
CY2017	us-gaap	Net Investment Income NetInvestmentIncome	3125000000	USD
CY2017	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	400000000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	260000000	USD
CY2017	cb	Segment Underwriting Income Lossand Net Investment Income Loss SegmentUnderwritingIncomeLossandNetInvestmentIncomeLoss	4555000000	USD
CY2017	cb	Net Realized Gains Losses NetRealizedGainsLosses	84000000	USD
CY2017	us-gaap	Interest Expense InterestExpense	607000000	USD
CY2017	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	310000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-139000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	3861000000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	31290000000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	30064000000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	29034000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4454000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	3962000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	3861000000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	455910463	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	463629203	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	467145716	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3004200	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3173145	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	4051185	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	458914663	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	466802348	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	471196901	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	9.77
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.55
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.26
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	9.71
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.49
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.19
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2410337	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	3543188	shares
CY2017	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1776025	shares
CY2019Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPayments	6500000000	USD
CY2019Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Required StatutoryAccountingPracticesStatutoryCapitalAndSurplusRequired	26300000000	USD
CY2018Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Required StatutoryAccountingPracticesStatutoryCapitalAndSurplusRequired	24200000000	USD
CY2019Q4	us-gaap	State Insurance Department Statutory To Naic Amount Of Reconciling Item StateInsuranceDepartmentStatutoryToNAICAmountOfReconcilingItem	147000000	USD
CY2018Q4	us-gaap	State Insurance Department Statutory To Naic Amount Of Reconciling Item StateInsuranceDepartmentStatutoryToNAICAmountOfReconcilingItem	160000000	USD
CY2019	us-gaap	Statutory Accounting Practices Permitted Practice Amount StatutoryAccountingPracticesPermittedPracticeAmount	54000000	USD
CY2018	us-gaap	Statutory Accounting Practices Permitted Practice Amount StatutoryAccountingPracticesPermittedPracticeAmount	178000000	USD
CY2019Q4	us-gaap	Investments Investments	109234000000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1537000000	USD
CY2019Q4	us-gaap	Restricted Cash RestrictedCash	109000000	USD
CY2019Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	10357000000	USD
CY2019Q4	cb	Reinsurance Recoverable Losses And Loss Expenses ReinsuranceRecoverableLossesAndLossExpenses	15181000000	USD
CY2019Q4	cb	Reinsurance Recoverable Future Policy Benefits ReinsuranceRecoverableFuturePolicyBenefits	197000000	USD
CY2019Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	306000000	USD
CY2019Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	21359000000	USD
CY2019Q4	cb	Investments In Subsidiaries To Be Eliminated Upon Consolidation InvestmentsInSubsidiariesToBeEliminatedUponConsolidation	0	USD
CY2019Q4	us-gaap	Due From Affiliates DueFromAffiliates	0	USD
CY2019Q4	cb	Other Assets Condensed OtherAssetsCondensed	18663000000	USD
CY2019Q4	us-gaap	Assets Assets	176943000000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	62690000000	USD
CY2019Q4	us-gaap	Unearned Premiums UnearnedPremiums	16771000000	USD
CY2019Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	5814000000	USD
CY2019Q4	us-gaap	Due To Affiliate Current And Noncurrent DueToAffiliateCurrentAndNoncurrent	0	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	1416000000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	1299000000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	13559000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	55331000000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	176943000000	USD
CY2019Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	308000000	USD
CY2019Q4	us-gaap	Other Liabilities OtherLiabilities	19755000000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	121612000000	USD
CY2018Q4	cb	Reinsurance Recoverable Future Policy Benefits ReinsuranceRecoverableFuturePolicyBenefits	202000000	USD
CY2018Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	295000000	USD
CY2018Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	509000000	USD
CY2018Q4	us-gaap	Investments Investments	100968000000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1247000000	USD
CY2018Q4	us-gaap	Restricted Cash RestrictedCash	93000000	USD
CY2018Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	10075000000	USD
CY2018Q4	cb	Reinsurance Recoverable Losses And Loss Expenses ReinsuranceRecoverableLossesAndLossExpenses	15993000000	USD
CY2018Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	21414000000	USD
CY2018Q4	cb	Investments In Subsidiaries To Be Eliminated Upon Consolidation InvestmentsInSubsidiariesToBeEliminatedUponConsolidation	0	USD
CY2018Q4	us-gaap	Due From Affiliates DueFromAffiliates	0	USD
CY2018Q4	cb	Other Assets Condensed OtherAssetsCondensed	17484000000	USD
CY2018Q4	us-gaap	Assets Assets	167771000000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	62960000000	USD
CY2018Q4	us-gaap	Unearned Premiums UnearnedPremiums	15532000000	USD
CY2018Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	5506000000	USD
CY2018Q4	us-gaap	Due To Affiliate Current And Noncurrent DueToAffiliateCurrentAndNoncurrent	0	USD
CY2018Q4	us-gaap	Bank Overdrafts BankOverdrafts	0	USD
CY2018Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	1418000000	USD
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	12087000000	USD
CY2018Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	308000000	USD
CY2018Q4	us-gaap	Other Liabilities OtherLiabilities	19139000000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	117459000000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	50312000000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	167771000000	USD
CY2019	us-gaap	Premiums Written Net PremiumsWrittenNet	32275000000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	31290000000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	3426000000	USD
CY2019	cb	Equity In Earnings Of Subsidiaries EquityInEarningsOfSubsidiaries	0	USD
CY2019	cb	Net Realized Gains Losses NetRealizedGainsLosses	-530000000	USD
CY2019	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	18730000000	USD
CY2019	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	740000000	USD
CY2019	cb	Policy Acquisition Costs And Administrative Expenses PolicyAcquisitionCostsAndAdministrativeExpenses	9183000000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-552000000	USD
CY2019	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	596000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	305000000	USD
CY2019	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	23000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	795000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4454000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	7521000000	USD
CY2018	us-gaap	Premiums Written Net PremiumsWrittenNet	30579000000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	30064000000	USD
CY2018	us-gaap	Net Investment Income NetInvestmentIncome	3305000000	USD
CY2018	cb	Equity In Earnings Of Subsidiaries EquityInEarningsOfSubsidiaries	0	USD
CY2018	cb	Net Realized Gains Losses NetRealizedGainsLosses	-652000000	USD
CY2018	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	18067000000	USD
CY2018	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	590000000	USD
CY2018	cb	Policy Acquisition Costs And Administrative Expenses PolicyAcquisitionCostsAndAdministrativeExpenses	8798000000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-641000000	USD
CY2018	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	434000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	339000000	USD
CY2018	us-gaap	Business Combination Integration Related Costs BusinessCombinationIntegrationRelatedCosts	59000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	695000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	3962000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1242000000	USD
CY2017	us-gaap	Premiums Written Net PremiumsWrittenNet	29244000000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	29034000000	USD
CY2018Q4	cb	Net Realized Gains Losses NetRealizedGainsLosses	-687000000	USD
CY2018Q1	us-gaap	Revenues Revenues	7831000000	USD
CY2018Q2	us-gaap	Revenues Revenues	8510000000	USD
CY2018Q3	us-gaap	Revenues Revenues	8750000000	USD
CY2018Q4	us-gaap	Revenues Revenues	7626000000	USD
CY2018Q1	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4102000000	USD
CY2018Q2	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4487000000	USD
CY2018Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4868000000	USD
CY2018Q4	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4610000000	USD
CY2018Q1	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	151000000	USD
CY2018Q2	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	150000000	USD
CY2018Q3	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	127000000	USD
CY2018Q4	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	162000000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	1082000000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	1294000000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	1231000000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	355000000	USD
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.32
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.78
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.66
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.77
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.30
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.76
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.64
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.76
CY2018Q4	us-gaap	Loss From Catastrophes LossFromCatastrophes	506000000	USD
CY2019Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Cost SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCost	106179000000	USD
CY2019Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Fair Value SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue	109511000000	USD
CY2019Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Carrying Amount SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCarryingAmount	109087000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1242000000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	4718000000	USD
CY2019	us-gaap	Direct Premiums Earned DirectPremiumsEarned	35876000000	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	7693000000	USD
CY2019	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	3107000000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	31290000000	USD
CY2019	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.10
CY2018	us-gaap	Direct Premiums Earned DirectPremiumsEarned	34108000000	USD
CY2018	us-gaap	Ceded Premiums Earned CededPremiumsEarned	7219000000	USD
CY2018	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	3175000000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	30064000000	USD
CY2018	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.11
CY2017	us-gaap	Direct Premiums Earned DirectPremiumsEarned	32782000000	USD
CY2017	us-gaap	Ceded Premiums Earned CededPremiumsEarned	7080000000	USD
CY2017	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	3332000000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	29034000000	USD
CY2017	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.11
CY2019Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Deferred Policy Acquisition Costs SupplementalInformationForPropertyCasualtyInsuranceUnderwritersDeferredPolicyAcquisitionCosts	4161000000	USD
CY2019Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Reserves For Unpaid Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersReservesForUnpaidClaimsAndClaimsAdjustmentExpense	48509000000	USD
CY2019Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Unearned Premiums SupplementalInformationForPropertyCasualtyInsuranceUnderwritersUnearnedPremiums	16771000000	USD
CY2019	us-gaap	Sec Schedule1218 Supplemental Information Property Casualty Insurance Underwriters Prior Year Claim And Claim Adjustment Expense SecSchedule1218SupplementalInformationPropertyCasualtyInsuranceUnderwritersPriorYearClaimAndClaimAdjustmentExpense	-845000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Amortization Of Deferred Policy Acquisition Costs SupplementalInformationForPropertyCasualtyInsuranceUnderwritersAmortizationOfDeferredPolicyAcquisitionCosts	5831000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Earned Premiums SupplementalInformationForPropertyCasualtyInsuranceUnderwritersEarnedPremiums	30189000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Net Investment Income SupplementalInformationForPropertyCasualtyInsuranceUnderwritersNetInvestmentIncome	3141000000	USD
CY2019	us-gaap	Sec Schedule1218 Supplemental Information Property Casualty Insurance Underwriters Current Year Claim And Claim Adjustment Expense SecSchedule1218SupplementalInformationPropertyCasualtyInsuranceUnderwritersCurrentYearClaimAndClaimAdjustmentExpense	19575000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Paid Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPaidClaimsAndClaimsAdjustmentExpense	18473000000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Premiums Written SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPremiumsWritten	31126000000	USD
CY2018Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Deferred Policy Acquisition Costs SupplementalInformationForPropertyCasualtyInsuranceUnderwritersDeferredPolicyAcquisitionCosts	3926000000	USD
CY2018Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Reserves For Unpaid Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersReservesForUnpaidClaimsAndClaimsAdjustmentExpense	48271000000	USD
CY2018Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Unearned Premiums SupplementalInformationForPropertyCasualtyInsuranceUnderwritersUnearnedPremiums	15532000000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Earned Premiums SupplementalInformationForPropertyCasualtyInsuranceUnderwritersEarnedPremiums	29042000000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Net Investment Income SupplementalInformationForPropertyCasualtyInsuranceUnderwritersNetInvestmentIncome	3047000000	USD
CY2017Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Deferred Policy Acquisition Costs SupplementalInformationForPropertyCasualtyInsuranceUnderwritersDeferredPolicyAcquisitionCosts	3805000000	USD
CY2017Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Reserves For Unpaid Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersReservesForUnpaidClaimsAndClaimsAdjustmentExpense	49165000000	USD
CY2017Q4	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Unearned Premiums SupplementalInformationForPropertyCasualtyInsuranceUnderwritersUnearnedPremiums	15216000000	USD
CY2018	us-gaap	Sec Schedule1218 Supplemental Information Property Casualty Insurance Underwriters Current Year Claim And Claim Adjustment Expense SecSchedule1218SupplementalInformationPropertyCasualtyInsuranceUnderwritersCurrentYearClaimAndClaimAdjustmentExpense	19048000000	USD
CY2018	us-gaap	Sec Schedule1218 Supplemental Information Property Casualty Insurance Underwriters Prior Year Claim And Claim Adjustment Expense SecSchedule1218SupplementalInformationPropertyCasualtyInsuranceUnderwritersPriorYearClaimAndClaimAdjustmentExpense	-981000000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Amortization Of Deferred Policy Acquisition Costs SupplementalInformationForPropertyCasualtyInsuranceUnderwritersAmortizationOfDeferredPolicyAcquisitionCosts	5630000000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Paid Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPaidClaimsAndClaimsAdjustmentExpense	18340000000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Premiums Written SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPremiumsWritten	29505000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Earned Premiums SupplementalInformationForPropertyCasualtyInsuranceUnderwritersEarnedPremiums	28054000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Net Investment Income SupplementalInformationForPropertyCasualtyInsuranceUnderwritersNetInvestmentIncome	2890000000	USD
CY2017	us-gaap	Sec Schedule1218 Supplemental Information Property Casualty Insurance Underwriters Current Year Claim And Claim Adjustment Expense SecSchedule1218SupplementalInformationPropertyCasualtyInsuranceUnderwritersCurrentYearClaimAndClaimAdjustmentExpense	19391000000	USD
CY2017	us-gaap	Sec Schedule1218 Supplemental Information Property Casualty Insurance Underwriters Prior Year Claim And Claim Adjustment Expense SecSchedule1218SupplementalInformationPropertyCasualtyInsuranceUnderwritersPriorYearClaimAndClaimAdjustmentExpense	-937000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Amortization Of Deferred Policy Acquisition Costs SupplementalInformationForPropertyCasualtyInsuranceUnderwritersAmortizationOfDeferredPolicyAcquisitionCosts	5519000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Paid Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPaidClaimsAndClaimsAdjustmentExpense	17448000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Premiums Written SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPremiumsWritten	28225000000	USD

Files In Submission

Name	View Source	Status
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0000896159-20-000003-index.html	Edgar Link	pending
0000896159-20-000003.txt	Edgar Link	pending
0000896159-20-000003-xbrl.zip	Edgar Link	pending
cb-12312019x10k.htm	Edgar Link	pending
cb-12312019x10k_htm.xml	Edgar Link	completed
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cb-12312019xex211.htm	Edgar Link	pending
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cb-12312019xex441.htm	Edgar Link	pending
cb-20191231.xsd	Edgar Link	pending
cb-20191231_cal.xml	Edgar Link	unprocessable
cb-20191231_def.xml	Edgar Link	unprocessable
cb-20191231_lab.xml	Edgar Link	unprocessable
cb-20191231_pre.xml	Edgar Link	unprocessable
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FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
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report.css	Edgar Link	pending
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$CB
Chubb Ltd Stock $cb

2019 Q4 Form 10-K Financial Statement

#000089615920000003 Filed on February 27, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CB Chubb Ltd Stock $cb

2019 Q4 Form 10-K Financial Statement

#000089615920000003 Filed on February 27, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CB
Chubb Ltd Stock $cb