$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc

$ambc Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000087450122000019 Filed on February 24, 2022

Income Statement

Concept	2021 Q4	2021	2020 Q4
Revenue	$56.00M	$282.0M	$53.00M
YoY Change	5.66%	80.77%	26.19%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin		$5.000M
YoY Change		25.0%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$12.00M	$57.00M	$17.00M
YoY Change	-29.41%	-1.72%	15.65%
% of Gross Profit
Operating Expenses	$31.00M	$94.00M	$50.00M
YoY Change	-38.0%	-74.87%	-63.34%
Operating Profit
YoY Change
Interest Expense	-$45.00M	-$192.0M	-$42.00M
YoY Change	7.14%	-15.04%	-37.03%
% of Operating Profit
Other Income/Expense, Net	$1.000M	$1.000M
YoY Change
Pretax Income	-$19.00M	-$32.00M	-$12.00M
YoY Change	58.33%	-92.74%	-89.19%
Income Tax	$3.000M	$18.00M	$2.000M
% Of Pretax Income
Net Earnings	-$20.00M	-$17.00M	-$14.00M
YoY Change	42.86%	-96.11%	-87.27%
Net Earnings / Revenue	-35.71%	-6.03%	-26.42%
Basic Earnings Per Share		-$0.61	-$0.31
Diluted Earnings Per Share	-$428.9K	-$0.61	-$0.31
COMMON SHARES
Basic Shares Outstanding	46.30M shares	46.54M shares	45.81M shares
Diluted Shares Outstanding		46.54M shares

Balance Sheet

Concept	2021 Q4	2021	2020 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$17.00M	$17.00M	$20.00M
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	$23.00M	$23.00M	$25.00M
YoY Change	-8.0%	-8.0%	0.0%
Goodwill	$46.00M		$46.00M
YoY Change	0.0%
Intangibles	$362.0M		$409.0M
YoY Change	-11.49%		-4.22%
Long-Term Investments	$9.128B	$9.128B	$51.00M
YoY Change	17798.04%	-7.76%	10.87%
Other Assets	$7.000M	$7.000M	$15.00M
YoY Change	-53.33%	-53.33%	-73.68%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$12.30B	$12.30B	$13.22B
YoY Change	-6.94%	-6.94%	-0.75%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$576.0M	$604.0M	$547.0M
YoY Change	5.3%	10.42%	16.14%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$576.0M	$604.0M	$553.0M
YoY Change	4.16%	9.22%	17.41%
LONG-TERM LIABILITIES
Long-Term Debt	$6.446B	$6.446B	$7.232B
YoY Change	-10.87%	-10.87%	-1.95%
Other Long-Term Liabilities	$2.167B	$2.139B	$2.023B
YoY Change	7.1%	5.71%	11.77%
Total Long-Term Liabilities	$8.613B	$8.585B	$9.255B
YoY Change	-6.94%	-7.24%	0.75%
TOTAL LIABILITIES
Total Short-Term Liabilities	$576.0M	$604.0M	$553.0M
Total Long-Term Liabilities	$8.613B	$8.585B	$9.255B
Total Liabilities	$11.19B	$11.26B	$12.07B
YoY Change	-7.35%	-7.22%	2.47%
SHAREHOLDERS EQUITY
Retained Earnings	$726.0M		$759.0M
YoY Change	-4.35%		-36.91%
Common Stock	$0.00		$0.00
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$3.000M		$1.000M
YoY Change	200.0%
Treasury Stock Shares	172.9K shares		55.94K shares
Shareholders Equity	$1.038B	$1.038B	$1.080B
YoY Change
Total Liabilities & Shareholders Equity	$12.30B	$12.30B	$13.22B
YoY Change	-6.94%	-6.94%	-0.75%

Cashflow Statement

Concept	2021 Q4	2021	2020 Q4
OPERATING ACTIVITIES
Net Income	-$20.00M	-$17.00M	-$14.00M
YoY Change	42.86%	-96.11%	-87.27%
Depreciation, Depletion And Amortization	$12.00M	$57.00M	$17.00M
YoY Change	-29.41%	-1.72%	15.65%
Cash From Operating Activities	$5.000M	-$131.0M	-$8.000M
YoY Change	-162.5%	-25.14%	-45.95%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions		$0.00
YoY Change		-100.0%
Other Investing Activities	$31.00M	$5.000M	$36.00M
YoY Change	-13.89%	-600.0%	-82.74%
Cash From Investing Activities	$31.00M	$776.0M	$36.00M
YoY Change	-13.89%	79.63%	-82.74%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-34.00M	-$657.0M	-43.00M
YoY Change	-20.93%	116.83%	-76.16%
NET CHANGE
Cash From Operating Activities	5.000M	-$131.0M	-8.000M
Cash From Investing Activities	31.00M	$776.0M	36.00M
Cash From Financing Activities	-34.00M	-$657.0M	-43.00M
Net Change In Cash	2.000M	-$12.00M	-15.00M
YoY Change	-113.33%	-73.91%	-211.94%
FREE CASH FLOW
Cash From Operating Activities	$5.000M	-$131.0M	-$8.000M
Capital Expenditures
Free Cash Flow
YoY Change

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2021	dei	Amendment Flag AmendmentFlag	false
CY2021	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2021	dei	Entity Central Index Key EntityCentralIndexKey	0000874501
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	32000	USD
CY2020Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	19000	USD
CY2021Q4	us-gaap	Equity Method Investments Fair Value Disclosure EquityMethodInvestmentsFairValueDisclosure	114000	USD
	ambc	Impactof Amt Repealon Current Taxes ImpactofAMTRepealonCurrentTaxes	29581000	USD
	ambc	Changein Impactof Amt Repealon Current Taxes ChangeinImpactofAMTRepealonCurrentTaxes	1902000	USD
	ambc	Amt Relatedto Filingof2017 Tax Return AMTRelatedtoFilingof2017TaxReturn	5536000	USD
CY2020Q4	ambc	Amt Receivable Resultingfrom Tcja AMTReceivableResultingfromTCJA	37019000	USD
	ambc	Net Impactof New Tax Law NetImpactofNewTaxLaw	1886000	USD
CY2021	dei	Document Type DocumentType	10-K
CY2021	dei	Document Annual Report DocumentAnnualReport	true
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Entity File Number EntityFileNumber	1-10777
CY2021	dei	Entity Registrant Name EntityRegistrantName	AMBAC FINANCIAL GROUP, INC.
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	13-3621676
CY2021	dei	Entity Address Address Line1 EntityAddressAddressLine1	One World Trade Center
CY2021	dei	Entity Address City Or Town EntityAddressCityOrTown	New York
CY2021	dei	Entity Address State Or Province EntityAddressStateOrProvince	NY
CY2021	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	10007
CY2021	dei	City Area Code CityAreaCode	(212)
CY2021	dei	Local Phone Number LocalPhoneNumber	658-7470
CY2021	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2021	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2021	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2021	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2021	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2021	dei	Entity Small Business EntitySmallBusiness	false
CY2021	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2021	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2021	dei	Entity Shell Company EntityShellCompany	false
CY2021Q2	dei	Entity Public Float EntityPublicFloat	723465112	USD
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CY2013Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2021	dei	Auditor Name AuditorName	KPMG LLP
CY2021	dei	Auditor Location AuditorLocation	New York, NY
CY2021	dei	Auditor Firm AuditorFirmId	185
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CY2021	us-gaap	Financing Receivable Allowance For Credit Losses Policy For Uncollectible Amounts FinancingReceivableAllowanceForCreditLossesPolicyForUncollectibleAmounts	<div style="margin-bottom:3pt;text-align:justify"><span style="color:#026dce;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:700;line-height:120%">Measurement of Credit Losses on Financial Instruments (CECL)</span></div><div style="margin-bottom:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">On January 1, 2020 Ambac adopted ASU 2016-13, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments-Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">subsequently amended by ASU 2018-19</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">, Codification Improvements to Topic 326, Financial Instruments - Credit Losses; </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">ASU 2019-04</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">, Codification Improvements to Topic 326, Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">; ASU 2019-05, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">; and ASU 2019-11, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Codification Improvements to Topic 326, Financial Instruments - Credit Losses (collectively the Current Expected Credit Loss standard or "CECL").</span></div><div style="margin-bottom:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The CECL standard affects how reporting entities measure credit losses for financial assets that are not accounted for at fair value through net income. For Ambac, these financial assets include available-for-sale debt securities and amortized cost assets, specifically premium receivables, reinsurance recoverables and loans. CECL does not apply to subrogation recoveries of previously paid and unpaid losses on insurance contracts accounted for under ASC 944 nor does it apply to equity method investments accounted for under ASC 323. </span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">For available-for-sale debt securities, credit losses under CECL are measured similarly to other-than-temporary impairments under prior GAAP. The updated guidance was applied prospectively. </span></div><div style="margin-bottom:9pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">For financial instruments measured at amortized cost, CECL replaces the "incurred loss" model, which generally delayed recognition of the full amount of credit losses until the loss was probable of occurring, with an "expected loss" model, which reflects an entity's current estimate of all expected lifetime credit losses. The estimate of expected lifetime credit losses should consider historical information, current information, as well as reasonable and supportable forecasts. Expected lifetime credit losses for amortized cost assets will be recorded as an allowance for credit losses, with subsequent increases or decreases in the allowance reflected in net income each period. The updated guidance was applied by a cumulative effect adjustment to the opening balance of retained earnings at January 1, 2020. This adjustment was not material to retained earnings </span></div>or any individual balance sheet line item. Refer to the discussion below for each asset type. As a result of adopting CECL, management revised its policies and procedures around the credit impairment evaluation process. CECL also introduced new disclosures related to the credit impairment process, including certain accounting policy elections that Ambac made under the new standard.
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CY2020Q4	ambc	Estimated Future Premium Payments Weighted Average Discounted Rate EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate	0.022
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CY2021	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2021	us-gaap	Impairment Of Intangible Assets Indefinitelived Excluding Goodwill ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	0	USD
CY2021Q4	us-gaap	Minority Interest MinorityInterest	60000000	USD
CY2021Q4	us-gaap	Business Acquisition Percentage Of Voting Interests Acquired BusinessAcquisitionPercentageOfVotingInterestsAcquired	0.80
CY2021Q4	ambc	Business Combination Redeemable Noncontrolling Percentage BusinessCombinationRedeemableNoncontrollingPercentage	0.20
CY2021Q4	ambc	Business Combination Redeemable Noncontrolling Percentage BusinessCombinationRedeemableNoncontrollingPercentage	0.20
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CY2020	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	7000000	USD
CY2021	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	-1000000	USD
CY2021	us-gaap	Temporary Equity Accretion To Redemption Value Adjustment TemporaryEquityAccretionToRedemptionValueAdjustment	12000000	USD
CY2021Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	18000000	USD
CY2020Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	7000000	USD
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-7000000	USD
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-1000000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	12000000	USD
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CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	11000000	USD
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CY2021Q4	ambc	Reduction In Long Term Debt Through Long Term Debt Exchange ReductionInLongTermDebtThroughLongTermDebtExchange	71000000	USD
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	17000000	USD
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CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	24000000	USD
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CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	35000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	81000000	USD
CY2021	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	Reclassifications and RoundingReclassifications may have been made to prior years' amounts to conform to the current year's presentation. Certain amounts and tables in the consolidated financial statements and associated notes may not add due to rounding.
CY2021Q4	us-gaap	Business Acquisition Percentage Of Voting Interests Acquired BusinessAcquisitionPercentageOfVotingInterestsAcquired	0.80
CY2021	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	81000000	USD
CY2021	ambc	Business Combination Goodwill Expected Tax Deductible Amount Accumulated Amortization BusinessCombinationGoodwillExpectedTaxDeductibleAmountAccumulatedAmortization	4000000	USD
CY2021Q4	ambc	Business Combination Redeemable Noncontrolling Percentage BusinessCombinationRedeemableNoncontrollingPercentage	0.20
CY2021Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	2140000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	141000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	16000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Current AvailableForSaleSecuritiesCurrent	2265000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	2807000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	149000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	8000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Current AvailableForSaleSecuritiesCurrent	2949000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	565000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	565000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	457000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	457000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	406000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	411000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	168000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	188000000	USD
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CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2140000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2265000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	768000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	14000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	41000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	810000000	USD
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	16000000	USD
CY2021Q4	ambc	Debt Securities Available For Sale Continuous Unrealized Loss Position DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition	783000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	14000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	41000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1000000	USD
CY2021Q4	ambc	Debt Securities Available For Sale Unrealized Loss Position Including Pledged Securities DebtSecuritiesAvailableForSaleUnrealizedLossPositionIncludingPledgedSecurities	825000000	USD
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	16000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	816000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	7000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	25000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	841000000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	8000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	816000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	7000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	25000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	841000000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	8000000	USD
CY2021	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	14000000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	38000000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	64000000	USD
CY2021	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	2000000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	12000000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	5000000	USD
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	0	USD
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	0	USD
CY2019	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	0	USD
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	0	USD
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	0	USD
CY2019	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	0	USD
CY2021	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	7000000	USD
CY2020	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	22000000	USD
CY2019	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	81000000	USD
CY2019Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	12000000	USD
CY2020	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	1000000	USD
CY2020Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	12000000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2021Q4	ambc	Fair Value Of Securities Deposited With Governmental Authorities FairValueOfSecuritiesDepositedWithGovernmentalAuthorities	17000000	USD
CY2020Q4	ambc	Fair Value Of Securities Deposited With Governmental Authorities FairValueOfSecuritiesDepositedWithGovernmentalAuthorities	8000000	USD
CY2021Q4	ambc	Fair Valueof Securities Depositedin Connectionwtih Letterof Credit FairValueofSecuritiesDepositedinConnectionwtihLetterofCredit	1000000	USD
CY2021Q4	ambc	Market Valueof Secured Note Collateral MarketValueofSecuredNoteCollateral	0	USD
CY2020Q4	ambc	Market Valueof Secured Note Collateral MarketValueofSecuredNoteCollateral	178000000	USD
CY2021Q4	ambc	Unsettled Amounts Secured Notes From Lsni UnsettledAmountsSecuredNotesFromLSNI	0	USD
CY2020Q4	ambc	Unsettled Amounts Secured Notes From Lsni UnsettledAmountsSecuredNotesFromLSNI	9000000	USD
CY2021Q4	ambc	Fair Value Of Securities Held By Ambac Uk Where Capital Stock Of Auk Is Pledged As Collateral For Sitka Aac Note FairValueOfSecuritiesHeldByAmbacUKWhereCapitalStockOfAUKIsPledgedAsCollateralForSitkaAACNote	669000000	USD
CY2021Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	8000000	USD
CY2020Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	0	USD
CY2020	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	103000000	USD
CY2019	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	183000000	USD
CY2021	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	USD
CY2020	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	USD
CY2019	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	USD
CY2021	us-gaap	Interest And Dividend Income Securities Available For Sale InterestAndDividendIncomeSecuritiesAvailableForSale	74000000	USD
CY2020	us-gaap	Interest And Dividend Income Securities Available For Sale InterestAndDividendIncomeSecuritiesAvailableForSale	103000000	USD
CY2019	us-gaap	Interest And Dividend Income Securities Available For Sale InterestAndDividendIncomeSecuritiesAvailableForSale	196000000	USD
CY2021	us-gaap	Net Investment Income NetInvestmentIncome	139000000	USD
CY2020	us-gaap	Net Investment Income NetInvestmentIncome	122000000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	227000000	USD
CY2021	us-gaap	Net Realized Or Unrealized Gain Loss On Trading Securities NetRealizedOrUnrealizedGainLossOnTradingSecurities	23000000	USD
CY2020	us-gaap	Net Realized Or Unrealized Gain Loss On Trading Securities NetRealizedOrUnrealizedGainLossOnTradingSecurities	0	USD
CY2019	us-gaap	Net Realized Or Unrealized Gain Loss On Trading Securities NetRealizedOrUnrealizedGainLossOnTradingSecurities	24000000	USD
CY2021	us-gaap	Trading Securities Realized Gain Loss TradingSecuritiesRealizedGainLoss	1000000	USD
CY2020	us-gaap	Trading Securities Realized Gain Loss TradingSecuritiesRealizedGainLoss	-18000000	USD
CY2019	us-gaap	Trading Securities Realized Gain Loss TradingSecuritiesRealizedGainLoss	7000000	USD
CY2021Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	8000000	USD
CY2020Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	0	USD
CY2021Q4	ambc	Fair Value Inputs Yield Rate FairValueInputsYieldRate	0.116
CY2021Q4	us-gaap	Number Of Credit Risk Derivatives Held NumberOfCreditRiskDerivativesHeld	1
CY2021	ambc	Fair Value Financial Assets And Liabilities Transfers In Or Out Of Level3 FairValueFinancialAssetsAndLiabilitiesTransfersInOrOutOfLevel3	0
CY2021Q4	ambc	Financial Guarantee Gross Outstanding Principal FinancialGuaranteeGrossOutstandingPrincipal	34122000000	USD
CY2020Q4	ambc	Financial Guarantee Gross Outstanding Principal FinancialGuaranteeGrossOutstandingPrincipal	39070000000	USD
CY2021Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	28020000000	USD
CY2020Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	33888000000	USD
CY2021Q4	ambc	Financial Guarantee Outstanding Principal Ceded To Third Parties FinancialGuaranteeOutstandingPrincipalCededToThirdParties	6102000000	USD
CY2021Q4	ambc	Amount Of Insured Par Outstanding Ceded To Reinsurer AmountOfInsuredParOutstandingCededToReinsurer	2695000000	USD
CY2021	ambc	Ceded Principal Outstanding Major Reinsurer Percentage CededPrincipalOutstandingMajorReinsurerPercentage	0.079
CY2021Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	28020000000	USD
CY2020Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	33888000000	USD
CY2021Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	28020000000	USD
CY2020Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	33888000000	USD
CY2021Q4	ambc	Financial Guarantee Gross Outstanding Principal And Interest FinancialGuaranteeGrossOutstandingPrincipalAndInterest	54272000000	USD
CY2020Q4	ambc	Financial Guarantee Gross Outstanding Principal And Interest FinancialGuaranteeGrossOutstandingPrincipalAndInterest	61895000000	USD
CY2021Q4	ambc	Net Financial Guarantee Principal And Interest In Force NetFinancialGuaranteePrincipalAndInterestInForce	42653000000	USD
CY2020Q4	ambc	Net Financial Guarantee Principal And Interest In Force NetFinancialGuaranteePrincipalAndInterestInForce	51603000000	USD
CY2021	ambc	Percentage Of Highest Single Insured Risk Of Aggregate Net Par Amount Guaranteed PercentageOfHighestSingleInsuredRiskOfAggregateNetParAmountGuaranteed	0.033
CY2021	us-gaap	Direct Premiums Written DirectPremiumsWritten	2000000	USD
CY2021	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	0	USD
CY2021	us-gaap	Ceded Premiums Written CededPremiumsWritten	35000000	USD
CY2021	us-gaap	Premiums Written Net PremiumsWrittenNet	-33000000	USD
CY2021	us-gaap	Direct Premiums Earned DirectPremiumsEarned	62000000	USD
CY2021	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	0	USD
CY2021	us-gaap	Ceded Premiums Earned CededPremiumsEarned	15000000	USD
CY2021	us-gaap	Premiums Earned Net PremiumsEarnedNet	47000000	USD
CY2020	us-gaap	Direct Premiums Written DirectPremiumsWritten	-1000000	USD
CY2020	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	0	USD
CY2020	us-gaap	Ceded Premiums Written CededPremiumsWritten	-1000000	USD
CY2020	us-gaap	Premiums Written Net PremiumsWrittenNet	0	USD
CY2020	us-gaap	Direct Premiums Earned DirectPremiumsEarned	65000000	USD
CY2020	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	1000000	USD
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	12000000	USD
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	54000000	USD
CY2019	us-gaap	Direct Premiums Written DirectPremiumsWritten	-28000000	USD
CY2019	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	0	USD
CY2021	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived	-35000000	USD
CY2020	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived	-46000000	USD
CY2019	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived	48000000	USD
CY2021	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-27000000	USD
CY2019	us-gaap	Ceded Premiums Written CededPremiumsWritten	31000000	USD
CY2019	us-gaap	Premiums Written Net PremiumsWrittenNet	-60000000	USD
CY2019	us-gaap	Direct Premiums Earned DirectPremiumsEarned	75000000	USD
CY2019	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	0	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	10000000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	66000000	USD
CY2021	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	1000000	USD
CY2020	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	12000000	USD
CY2019	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	10000000	USD
CY2021	us-gaap	Premiums Earned Net Financial Guarantee Insurance Contracts PremiumsEarnedNetFinancialGuaranteeInsuranceContracts	47000000	USD
CY2020	us-gaap	Premiums Earned Net Financial Guarantee Insurance Contracts PremiumsEarnedNetFinancialGuaranteeInsuranceContracts	54000000	USD
CY2019	us-gaap	Premiums Earned Net Financial Guarantee Insurance Contracts PremiumsEarnedNetFinancialGuaranteeInsuranceContracts	66000000	USD
CY2021Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	323000000	USD
CY2020Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	370000000	USD
CY2021Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	329000000	USD
CY2020Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	387000000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	17000000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	9000000	USD
CY2021	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-6000000	USD
CY2020	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	9000000	USD
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	-2000000	USD
CY2020	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	-2000000	USD
CY2021Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	9000000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	17000000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	9000000	USD
CY2020Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	370000000	USD
CY2019Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	416000000	USD
CY2018Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	495000000	USD
CY2020	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-6000000	USD
CY2019	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-38000000	USD
CY2021	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable	8000000	USD
CY2020	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable	9000000	USD
CY2019	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable	11000000	USD
CY2021	ambc	Financial Guarantee Insurance Contracts Premium Receivable Deconsolidationof Vie FinancialGuaranteeInsuranceContractsPremiumReceivableDeconsolidationofVIE	0	USD
CY2020	ambc	Financial Guarantee Insurance Contracts Premium Receivable Deconsolidationof Vie FinancialGuaranteeInsuranceContractsPremiumReceivableDeconsolidationofVIE	0	USD
CY2019	ambc	Financial Guarantee Insurance Contracts Premium Receivable Deconsolidationof Vie FinancialGuaranteeInsuranceContractsPremiumReceivableDeconsolidationofVIE	3000000	USD
CY2021	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	8000000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	-4000000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	-2000000	USD
CY2021	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments	-4000000	USD
CY2020	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments	5000000	USD
CY2019	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments	-6000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	320000000	USD
CY2020Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	370000000	USD
CY2019Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	416000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During First Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFirstQuarterFollowingBalanceSheetDate	10000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During First Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFirstQuarterFollowingBalanceSheetDate	7000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Second Quarter Following The Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringSecondQuarterFollowingTheBalanceSheetDate	7000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Second Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringSecondQuarterFollowingBalanceSheetDate	7000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Third Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringThirdQuarterFollowingBalanceSheetDate	9000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Third Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringThirdQuarterFollowingBalanceSheetDate	7000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Fourth Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFourthQuarterFollowingBalanceSheetDate	7000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Fourth Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFourthQuarterFollowingBalanceSheetDate	7000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than One And Within Two Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanOneAndWithinTwoYearsFromBalanceSheetDate	32000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than One And Within Two Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanOneAndWithinTwoYearsFromBalanceSheetDate	25000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Two And Within Three Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanTwoAndWithinThreeYearsFromBalanceSheetDate	30000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Two And Within Three Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanTwoAndWithinThreeYearsFromBalanceSheetDate	24000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Three And Within Four Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanThreeAndWithinFourYearsFromBalanceSheetDate	29000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Three And Within Four Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanThreeAndWithinFourYearsFromBalanceSheetDate	23000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Four And Within Five Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate	28000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Four And Within Five Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate	22000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Five And Within10 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFiveAndWithin10YearsFromBalanceSheetDate	113000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Five And Within10 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFiveAndWithin10YearsFromBalanceSheetDate	91000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than10 And Within15 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan10AndWithin15YearsFromBalanceSheetDate	75000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than10 And Within15 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan10AndWithin15YearsFromBalanceSheetDate	57000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than15 And Within20 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan15AndWithin20YearsFromBalanceSheetDate	32000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than15 And Within20 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan15AndWithin20YearsFromBalanceSheetDate	22000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than20 And Within25 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan20AndWithin25YearsFromBalanceSheetDate	15000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than20 And Within25 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan20AndWithin25YearsFromBalanceSheetDate	9000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than25 And Within30 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan25AndWithin30YearsFromBalanceSheetDate	5000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than25 And Within30 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan25AndWithin30YearsFromBalanceSheetDate	3000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than30 And Within35 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan30AndWithin35YearsFromBalanceSheetDate	0	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than30 And Within35 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan30AndWithin35YearsFromBalanceSheetDate	0	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Premium Expected To Be Collected FinancialGuaranteeInsuranceContractsPremiumReceivablePremiumExpectedToBeCollected	393000000	USD
CY2021Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognized	303000000	USD
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1570000000	USD
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1759000000	USD
CY2021Q4	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	2092000000	USD
CY2020Q4	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	2156000000	USD
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionClaimLiability	-522000000	USD
CY2020Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionClaimLiability	-397000000	USD
CY2021	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="margin-bottom:3pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">Below is the loss and loss reserve expense roll-forward, net of subrogation recoverable and reinsurance, for the affected periods.</span></div><div style="margin-bottom:6pt;text-align:justify"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"/><td style="width:44.733%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:15.887%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:1.402%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:15.887%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:1.402%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:15.889%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Year Ended December 31,</span></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2021</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2019</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Beginning gross loss and loss expense reserves</span></div></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(397)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(482)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(107)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Reinsurance recoverable</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">33</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">26 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">23 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Beginning balance of net loss and loss expense reserves</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(430)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(508)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(130)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Losses and loss expenses (benefit) incurred:</span></div></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:11.25pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Current year</span></div></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">15 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 12.25pt;text-align:left;text-indent:-4.5pt;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Prior years</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(89)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">210 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">12 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(1)(2)</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(88)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">225 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">13 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Loss and loss expenses (recovered) paid:</span></div></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:11.25pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Current year</span></div></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 12.25pt;text-align:left;text-indent:-4.5pt;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Prior years</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">59</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">148 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">318 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">59</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">149 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">318 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Foreign exchange effect</span></div></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">2 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(1)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Ending net loss and loss expense reserves</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(577)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(430)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(436)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Impact of VIE consolidation</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(72)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Reinsurance recoverable </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(3)</span></div></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">55</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">33 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">26 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Ending gross loss and loss expense reserves</span></div></td><td colspan="2" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(522)</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(397)</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(482)</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div><div style="margin-top:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(1)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Total losses and loss expenses (benefit) includes $5, $(11) and $(7) for the years ended December 31, 2021, 2020 and 2019, respectively, related to ceded reinsurance.</span></div><div style="margin-bottom:3pt;margin-top:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(2)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Ambac records the impact of estimated recoveries related to securitized loans in RMBS transactions that breached certain R&W's by transaction sponsors within losses and loss expenses (benefit). The losses and loss expense (benefit) incurred associated with changes in estimated R&W's recoveries for the year ended December 31, 2021, 2020 and 2019 was $20, $(23) and $42, respectively.</span></div><div style="margin-bottom:9pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(3)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Represents reinsurance recoverable on future loss and loss expenses. Additionally, the Balance Sheet line "Reinsurance recoverable on paid and unpaid losses" includes reinsurance recoverables (payables) of $0, $1 and $0 as of December 31, 2021, 2020 and 2019, respectively, related to previously presented loss and loss expenses and subrogation.</span></div>
CY2020Q4	ambc	Liability For Claims And Claims Adjustment Expense Net Of Reinsurance Recoverables LiabilityForClaimsAndClaimsAdjustmentExpenseNetOfReinsuranceRecoverables	-397000000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	-482000000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	-107000000	USD
CY2020Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	33000000	USD
CY2019Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	26000000	USD
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CY2021Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Derivative Net Assets Or Liabilities VariableInterestEntityNonconsolidatedCarryingAmountDerivativeNetAssetsOrLiabilities	5000000	USD
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CY2020Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Assets VariableInterestEntityNonconsolidatedCarryingAmountInsuranceAssets	2314000000	USD
CY2020Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Liabilities VariableInterestEntityNonconsolidatedCarryingAmountInsuranceLiabilities	1122000000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	51000000	USD
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CY2021Q4	ambc	Reb Warranty Subrogation Recoveries Up To RebWarrantySubrogationRecoveriesUpTo	1400000000	USD
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CY2018Q1	ambc	Tier2 Note Securityin Rmbs Litigation Settlement Proceeds Tier2NoteSecurityinRMBSLitigationSettlementProceeds	1600000000	USD
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CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46535001	shares
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CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	12000000	USD
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CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1000000	USD
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CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	2000000	USD
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CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18000000	USD
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CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
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CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	134000000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	152000000	USD
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CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	886000000	USD
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CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	128000000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	28000000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	24000000	USD
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CY2021	us-gaap	Postemployment Benefits Period Expense PostemploymentBenefitsPeriodExpense	1000000	USD
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CY2019	us-gaap	Postemployment Benefits Period Expense PostemploymentBenefitsPeriodExpense	3000000	USD
CY2021Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Year Two DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo	0	USD
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CY2021Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Year Four DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour	1000000	USD
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CY2021Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Five Fiscal Years Thereafter DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter	3000000	USD
CY2021Q4	us-gaap	Defined Benefit Plan Benefit Obligation DefinedBenefitPlanBenefitObligation	5000000	USD
CY2021Q4	us-gaap	Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate	0.0275
CY2020Q4	us-gaap	Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate	0.0225
CY2021Q4	us-gaap	Postemployment Benefits Liability Current And Noncurrent PostemploymentBenefitsLiabilityCurrentAndNoncurrent	11000000	USD
CY2021Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Next Twelve Months DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths	0	USD
CY2021	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Percent DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent	0.02
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1000000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1000000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1000000	USD
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	1255643	shares
CY2021Q4	ambc	Share Based Compensation Arrangement Shares Availablefor Future Issuanceat Target ShareBasedCompensationArrangementSharesAvailableforFutureIssuanceatTarget	2691618	shares
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	14000000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11000000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12000000	USD
CY2021	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	14000000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	11000000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	12000000	USD
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	504764	shares
CY2021Q4	ambc	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Restricted Stock Units Vested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsRestrictedStockUnitsVestedNumber	332306	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	345302	shares
CY2020Q4	ambc	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Restricted Stock Units Vested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsRestrictedStockUnitsVestedNumber	428355	shares
CY2021Q4	ambc	Total Shareholder Return Modifier TotalShareholderReturnModifier	0.10
CY2021Q4	ambc	Psu Payout Percentage Upon Termination PSUPayoutPercentageUponTermination	1
CY2021	ambc	Performance Awards Settlement Period PerformanceAwardsSettlementPeriod	P75D
CY2021	us-gaap	Operating Lease Expense OperatingLeaseExpense	5000000	USD
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	4000000	USD
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	0	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	0	USD
CY2021	us-gaap	Sublease Income SubleaseIncome	-1000000	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	-1000000	USD
CY2021	us-gaap	Lease Cost LeaseCost	4000000	USD
CY2020	us-gaap	Lease Cost LeaseCost	4000000	USD
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	5000000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	4000000	USD
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	23000000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	25000000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	28000000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	30000000	USD
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y8M12D
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y8M12D
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CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.077
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	5000000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	5000000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	5000000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	5000000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	4000000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	14000000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	37000000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	-9000000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	28000000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Term Of Contract LessorOperatingLeaseTermOfContract	P8Y
CY2021Q4	us-gaap	Operating Leases Future Minimum Payments Receivable Remainder Of Fiscal Year OperatingLeasesFutureMinimumPaymentsReceivableRemainderOfFiscalYear	1000000	USD
CY2021Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Cost SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCost	2734000000	USD
CY2021Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	4000000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	10000000	USD
CY2021Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Two Years OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears	1000000	USD
CY2021Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Three Years OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears	1000000	USD
CY2021Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Four Years OperatingLeasesFutureMinimumPaymentsReceivableInFourYears	1000000	USD
CY2021Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Five Years OperatingLeasesFutureMinimumPaymentsReceivableInFiveYears	1000000	USD
CY2021Q4	ambc	Investment Excluding Related Party Investments InvestmentExcludingRelatedPartyInvestments	2955000000	USD
CY2021Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	8000000	USD
CY2013Q2	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2021Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	20000000	shares
CY2021Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	20000000	shares
CY2021Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2013Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2013Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2021Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	130000000	shares
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	130000000	shares
CY2021Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	46477068	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	45865081	shares
CY2021Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	172929	shares
CY2020Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	55942	shares
CY2021	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	-12000000	USD
CY2021	us-gaap	Proceeds From Contributions From Affiliates ProceedsFromContributionsFromAffiliates	6000000	USD
CY1991Q2	dei	Entity Incorporation Date Of Incorporation EntityIncorporationDateOfIncorporation	1991-04-29
CY2021Q4	us-gaap	Business Acquisition Percentage Of Voting Interests Acquired BusinessAcquisitionPercentageOfVotingInterestsAcquired	0.80
CY2021	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	81000000	USD
CY2021Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	3744000000	USD
CY2021	us-gaap	Direct Premiums Written DirectPremiumsWritten	2000000	USD
CY2021	us-gaap	Ceded Premiums Written CededPremiumsWritten	35000000	USD
CY2021	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	0	USD
CY2021	us-gaap	Premiums Written Net PremiumsWrittenNet	-33000000	USD
CY2021	ambc	Ambc Premiums Written Financial Guarantee Insurance Contracts Percentage Of Amount Assumed To Net Ambc_PremiumsWrittenFinancialGuaranteeInsuranceContractsPercentageOfAmountAssumedToNet	0	Rate
CY2020	us-gaap	Direct Premiums Written DirectPremiumsWritten	-1000000	USD
CY2020	us-gaap	Ceded Premiums Written CededPremiumsWritten	-1000000	USD
CY2020	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	0	USD
CY2020	us-gaap	Premiums Written Net PremiumsWrittenNet	0	USD
CY2020	ambc	Ambc Premiums Written Financial Guarantee Insurance Contracts Percentage Of Amount Assumed To Net Ambc_PremiumsWrittenFinancialGuaranteeInsuranceContractsPercentageOfAmountAssumedToNet	0	Rate
CY2019	us-gaap	Direct Premiums Written DirectPremiumsWritten	-28000000	USD
CY2019	us-gaap	Ceded Premiums Written CededPremiumsWritten	31000000	USD
CY2019	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	0	USD
CY2019	us-gaap	Premiums Written Net PremiumsWrittenNet	-60000000	USD
CY2019	ambc	Ambc Premiums Written Financial Guarantee Insurance Contracts Percentage Of Amount Assumed To Net Ambc_PremiumsWrittenFinancialGuaranteeInsuranceContractsPercentageOfAmountAssumedToNet	0	Rate

Files In Submission

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$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc

2021 Q4 Form 10-K Financial Statement

#000087450122000019 Filed on February 24, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMBC AMBAC FINANCIAL GROUP INC Stock $ambc

2021 Q4 Form 10-K Financial Statement

#000087450122000019 Filed on February 24, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc