$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc

$ambc Overview Financials Valuation SEC Filings Company Website

2023 Q1 Form 10-K Financial Statement

#000087450123000040 Filed on March 01, 2023

Income Statement

Concept	2023 Q1	2022 Q4	2022
Revenue	$58.00M	$72.00M	$505.0M
YoY Change	-51.26%	28.57%	79.08%
Cost Of Revenue	$18.00M		-$396.0M
YoY Change	-25.0%
Gross Profit	$40.00M		$901.0M
YoY Change	-57.89%
Gross Profit Margin	68.97%		178.42%
Selling, General & Admin	$36.00M	$51.00M	$141.0M
YoY Change			2720.0%
% of Gross Profit	90.0%		15.65%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$0.00	$14.00M	$2.000M
YoY Change		16.67%	-96.49%
% of Gross Profit	0.0%		0.22%
Operating Expenses	$66.00M	$12.00M	$139.0M
YoY Change	127.59%	-61.29%	47.87%
Operating Profit	-$26.00M		$762.0M
YoY Change	-139.39%
Interest Expense	$16.00M	-$36.00M	$168.0M
YoY Change	-63.64%	-20.0%	-187.5%
% of Operating Profit			22.05%
Other Income/Expense, Net	-$2.000M	-$1.000M	-$3.000M
YoY Change		-200.0%	-400.0%
Pretax Income	-$29.00M	$173.0M	$525.0M
YoY Change	-1066.67%	-1010.53%	-1740.63%
Income Tax	$4.000M	-$2.000M	$2.000M
% Of Pretax Income		-1.16%	0.38%
Net Earnings	-$33.00M	$178.0M	$522.0M
YoY Change	-1750.0%	-990.0%	-3170.59%
Net Earnings / Revenue	-56.9%	247.22%	103.37%
Basic Earnings Per Share	-$0.73		$11.48
Diluted Earnings Per Share	-$0.73	$3.82	$11.31
COMMON SHARES
Basic Shares Outstanding	45.29M shares	44.97M shares	45.72M shares
Diluted Shares Outstanding	45.56M shares		46.41M shares

Balance Sheet

Concept	2023 Q1	2022 Q4	2022
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.961B	$1.997B
YoY Change
Cash & Equivalents	$38.00M	$31.00M	$44.00M
Short-Term Investments	$1.923B	$1.966B
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment		$21.00M	$21.00M
YoY Change		-8.7%	-8.7%
Goodwill	$61.00M	$61.00M
YoY Change	32.61%	32.61%
Intangibles	$321.0M	$326.0M
YoY Change	-8.29%	-9.94%
Long-Term Investments	$6.484B	$6.389B	$6.389B
YoY Change	-25.02%	-30.01%	-30.01%
Other Assets	$256.0M	$17.00M	$17.00M
YoY Change	357.14%	142.86%	142.86%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$8.219B	$7.973B	$7.973B
YoY Change	-28.72%	-35.19%	-35.19%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$438.0M	$452.0M	$452.0M
YoY Change	-26.14%	-21.53%	-25.17%
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	$438.0M	$452.0M	$452.0M
YoY Change	-26.14%	-21.53%	-25.17%
LONG-TERM LIABILITIES
Long-Term Debt	$3.557B	$3.746B	$3.746B
YoY Change	-44.13%	-41.89%	-41.89%
Other Long-Term Liabilities	$1.620B	$1.235B	$1.235B
YoY Change	-22.16%	-43.02%	-42.27%
Total Long-Term Liabilities	$5.177B	$4.981B	$4.981B
YoY Change	-38.71%	-42.17%	-41.98%
TOTAL LIABILITIES
Total Short-Term Liabilities	$438.0M	$452.0M	$452.0M
Total Long-Term Liabilities	$5.177B	$4.981B	$4.981B
Total Liabilities	$6.892B	$6.647B	$6.722B
YoY Change	-34.6%	-40.58%	-40.33%
SHAREHOLDERS EQUITY
Retained Earnings	$1.206B	$1.245B
YoY Change	66.8%	71.49%
Common Stock	$0.00	$0.00
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$14.00M	$15.00M
YoY Change	600.0%	400.0%
Treasury Stock Shares		1.685M shares
Shareholders Equity	$1.254B	$1.252B	$1.251B
YoY Change
Total Liabilities & Shareholders Equity	$8.219B	$7.973B	$7.973B
YoY Change	-28.72%	-35.19%	-35.19%

Cashflow Statement

Concept	2023 Q1	2022 Q4	2022
OPERATING ACTIVITIES
Net Income	-$33.00M	$178.0M	$522.0M
YoY Change	-1750.0%	-990.0%	-3170.59%
Depreciation, Depletion And Amortization	$0.00	$14.00M	$2.000M
YoY Change		16.67%	-96.49%
Cash From Operating Activities	$77.00M	$1.277B	$1.335B
YoY Change	755.56%	25440.0%	-1119.08%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions			-$18.00M
YoY Change
Other Investing Activities	-$8.000M	$431.0M	-$9.000M
YoY Change		1290.32%	-280.0%
Cash From Investing Activities	$441.0M	$431.0M	$866.0M
YoY Change	224.26%	1290.32%	11.6%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			-$14.20M
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-$276.0M	-1.684B	-$2.163B
YoY Change	430.77%	4852.94%	229.22%
NET CHANGE
Cash From Operating Activities	$77.00M	1.277B	$1.335B
Cash From Investing Activities	$441.0M	431.0M	$866.0M
Cash From Financing Activities	-$276.0M	-1.684B	-$2.163B
Net Change In Cash	$243.0M	24.00M	$38.00M
YoY Change	161.29%	1100.0%	-416.67%
FREE CASH FLOW
Cash From Operating Activities	$77.00M	$1.277B	$1.335B
Capital Expenditures
Free Cash Flow
YoY Change

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2022	dei	Amendment Flag AmendmentFlag	false
CY2022	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2022
CY2022	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2022	dei	Entity Central Index Key EntityCentralIndexKey	0000874501
CY2022	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2022Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	32000	usd
CY2021Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	19000	usd
CY2022Q4	us-gaap	Equity Method Investments Fair Value Disclosure EquityMethodInvestmentsFairValueDisclosure	0	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
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	ambc	Net Impactof New Tax Law NetImpactofNewTaxLaw	1886000	usd
CY2022	dei	Document Type DocumentType	10-K
CY2022	dei	Document Annual Report DocumentAnnualReport	true
CY2022	dei	Document Period End Date DocumentPeriodEndDate	2022-12-31
CY2022	dei	Document Transition Report DocumentTransitionReport	false
CY2022	dei	Entity Shell Company EntityShellCompany	false
CY2022	dei	Entity File Number EntityFileNumber	1-10777
CY2022	dei	Entity Registrant Name EntityRegistrantName	AMBAC FINANCIAL GROUP, INC.
CY2022	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2022	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	13-3621676
CY2022	dei	Entity Address Address Line1 EntityAddressAddressLine1	One World Trade Center
CY2022	dei	Entity Address City Or Town EntityAddressCityOrTown	New York
CY2022	dei	Entity Address State Or Province EntityAddressStateOrProvince	NY
CY2022	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	10007
CY2022	dei	City Area Code CityAreaCode	(212)
CY2022	dei	Local Phone Number LocalPhoneNumber	658-7470
CY2022	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2022	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2022	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2022	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2022	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2022	dei	Entity Small Business EntitySmallBusiness	false
CY2022	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2022	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2022Q2	dei	Entity Public Float EntityPublicFloat	510068047	usd
CY2023Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	45287112	shares
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CY1991Q2	dei	Entity Incorporation Date Of Incorporation EntityIncorporationDateOfIncorporation	1991-04-29
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CY2022	dei	Auditor Name AuditorName	KPMG LLP
CY2022	dei	Auditor Location AuditorLocation	New York, NY
CY2022	dei	Auditor Firm AuditorFirmId	185
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CY2022Q4	us-gaap	Short Term Investments ShortTermInvestments	507000000	usd
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CY2021Q4	us-gaap	Other Investments OtherInvestments	690000000	usd
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CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	525000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-440000000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18000000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3000000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	522000000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	-16000000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	-437000000	usd
CY2022	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	-1000000	usd
CY2021	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	-1000000	usd
CY2022	ambc	Amps Gain On Purchase Of Shares AMPSGainOnPurchaseOfShares	1000000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	522000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	-17000000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-437000000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	522000000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	-16000000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	-437000000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-225000000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-12000000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	15000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-85000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-8000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	23000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionReclassificationAdjustmentFromAociForDerecognitionAfterTax	0	usd
CY2021	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionReclassificationAdjustmentFromAociForDerecognitionAfterTax	1000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionReclassificationAdjustmentFromAociForDerecognitionAfterTax	-1000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	1000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	1000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	3000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-310000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-21000000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	37000000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	212000000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-38000000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-400000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-1000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-1000000	usd
CY2022	ambc	Amps Gain On Purchase Of Shares AMPSGainOnPurchaseOfShares	1000000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	212000000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-38000000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-400000000	usd
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	11.48
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.61
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-9.47
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	11.31
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.61
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-9.47
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	45719906	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46535001	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46147062	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46414830	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46535001	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46147062	shares
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1536000000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-400000000	usd
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11000000	usd
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-3000000	usd
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1140000000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-38000000	usd
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	14000000	usd
CY2021	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-6000000	usd
CY2021	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	-12000000	usd
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1098000000	usd
CY2022	ambc	Comprehensive Income Loss Net Of Tax Including Portion Attributable To Noncontrolling Interest Total Excluding Gain On Amps Repurchase ComprehensiveIncomeLossNetOfTaxIncludingPortionAttributableToNoncontrollingInterestTotalExcludingGainOnAMPSRepurchase	211000000	usd
CY2022	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	17000000	usd
CY2022	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-4000000	usd
CY2022	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	-14000000	usd
CY2022	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	3000000	usd
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CY2022	ambc	Amps Impacton Stockholders Equity AMPSImpactonStockholdersEquity	-8000000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1305000000	usd
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CY2022	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-1000000	usd
CY2021	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-1000000	usd
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CY2021	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	-82000000	usd
CY2020	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	-48000000	usd
CY2022	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	-1220000000	usd
CY2021	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	147000000	usd
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CY2022	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	403000000	usd
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CY2022	ambc	Proceeds From Financial Guaranty Variable Interest Entity Assets ProceedsFromFinancialGuarantyVariableInterestEntityAssets	504000000	usd
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CY2022	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	-18000000	usd
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	usd
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CY2022	ambc	Paydownof Financial Guaranty Variable Interest Entity Liabilities PaydownofFinancialGuarantyVariableInterestEntityLiabilities	591000000	usd
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CY2020	ambc	Paydownof Financial Guaranty Variable Interest Entity Liabilities PaydownofFinancialGuarantyVariableInterestEntityLiabilities	178000000	usd
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CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-657000000	usd
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-303000000	usd
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CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	38000000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-12000000	usd
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-46000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	23000000	usd
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
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	61000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	23000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	35000000	usd
CY1991Q2	dei	Entity Incorporation Date Of Incorporation EntityIncorporationDateOfIncorporation	1991-04-29
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CY1991Q2	ambc	Common Stock Voting Restrictions CommonStockVotingRestrictions	0.10
CY1991Q2	ambc	Common Stock Voting Restriction Less One Vote CommonStockVotingRestrictionLessOneVote	0.10
CY1991Q2	ambc	Common Stock Transfer Restrictions CommonStockTransferRestrictions	0.05
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CY2018Q1	ambc	Tier2 Note Securityin Rmbs Litigation Settlement Proceeds Tier2NoteSecurityinRMBSLitigationSettlementProceeds	1600000000	usd
CY2018Q1	ambc	Tier2 Note Securityin Rmbs Litigation Settlement Proceeds Tier2NoteSecurityinRMBSLitigationSettlementProceeds	1600000000	usd
CY2022	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%">Ambac measures credit losses on financial assets that are not accounted for at fair value through net income in accordance with the Current Expected Credit Loss standard or "CECL". The CECL impact on available-for-sale debt securities is discussed in the Investments sub-section below. </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 impact on amortized cost assets is addressed in the Premium, Reinsurance Recoverables and Loan sub-sections below. These amortized cost assets reflect management's current estimate of all expected lifetime credit losses. The estimate of expected lifetime credit losses considers historical information, current information, as well as reasonable and supportable forecasts. Expected lifetime credit losses for amortized cost assets are recorded as an allowance for credit losses, with subsequent increases or decreases in the allowance reflected in net income each period.</span></div>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.
CY2022Q4	ambc	Cecl Securities Factor For Consideration CECLSecuritiesFactorForConsideration	0.20
CY2022Q4	ambc	Estimated Future Premium Payments Weighted Average Discounted Rate EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate	0.030
CY2021Q4	ambc	Estimated Future Premium Payments Weighted Average Discounted Rate EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate	0.022
CY2022	us-gaap	Financial Guarantee Insurance Contracts Premium Received Over Contract Period Premium Receivable Weighted Average Collection Period1 FinancialGuaranteeInsuranceContractsPremiumReceivedOverContractPeriodPremiumReceivableWeightedAverageCollectionPeriod1	P8Y
CY2021	us-gaap	Financial Guarantee Insurance Contracts Premium Received Over Contract Period Premium Receivable Weighted Average Collection Period1 FinancialGuaranteeInsuranceContractsPremiumReceivedOverContractPeriodPremiumReceivableWeightedAverageCollectionPeriod1	P8Y
CY2022Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	usd
CY2022	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	usd
CY2022	us-gaap	Impairment Of Intangible Assets Indefinitelived Excluding Goodwill ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	0	usd
CY2021	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	-1000000	usd
CY2022Q4	us-gaap	Minority Interest MinorityInterest	53000000	usd
CY2021Q4	us-gaap	Minority Interest MinorityInterest	60000000	usd
CY2022	ambc	Amps Shares Purchased AMPSSharesPurchased	-905
CY2022	ambc	Amps Purchase Cash Paid AMPSPurchaseCashPaid	8000000	usd
CY2022	ambc	Amps Gain Based On Carry Value AMPSGainBasedOnCarryValue	1000000	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
CY2022Q4	us-gaap	Business Combination Acquisition Of Less Than100 Percent Noncontrolling Interest Fair Value BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue	5000000	usd
CY2021Q4	us-gaap	Business Combination Acquisition Of Less Than100 Percent Noncontrolling Interest Fair Value BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue	0	usd
CY2022	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	-1000000	usd
CY2022	us-gaap	Temporary Equity Accretion To Redemption Value Adjustment TemporaryEquityAccretionToRedemptionValueAdjustment	-3000000	usd
CY2021	us-gaap	Temporary Equity Accretion To Redemption Value Adjustment TemporaryEquityAccretionToRedemptionValueAdjustment	12000000	usd
CY2022Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	20000000	usd
CY2021Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	18000000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	11000000	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
CY2021Q2	ambc	Uk Income Tax Rate UKIncomeTaxRate	0.19
CY2019Q3	ambc	Uk Income Tax Rate UKIncomeTaxRate	0.25
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	6000000	usd
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	15000000	usd
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	11000000	usd
CY2021	ambc	Decrease In Long Term Debt As A Result Of Surplus Notes Exchanges DecreaseInLongTermDebtAsAResultOfSurplusNotesExchanges	71000000	usd
CY2022	ambc	Securities Acquired In Transactions Related To Puerto Rico Restructurings SecuritiesAcquiredInTransactionsRelatedToPuertoRicoRestructurings	508000000	usd
CY2022	ambc	Loans Acquired Through Financial Guarantee Subrogation LoansAcquiredThroughFinancialGuaranteeSubrogation	20000000	usd
CY2022	ambc	Vie Long Term Debt Issued Related To Puerto Rico Restructurings VIELongTermDebtIssuedRelatedToPuertoRicoRestructurings	583000000	usd
CY2022Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	31000000	usd
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	17000000	usd
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	20000000	usd
CY2022Q4	us-gaap	Restricted Cash RestrictedCash	14000000	usd
CY2021Q4	us-gaap	Restricted Cash RestrictedCash	5000000	usd
CY2020Q4	us-gaap	Restricted Cash RestrictedCash	13000000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	61000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	23000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	35000000	usd
CY2022	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<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%">Reclassifications and Rounding</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%">Reclassifications 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.</span></div>
CY2022	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3
CY2022	us-gaap	Premiums Earned Net PremiumsEarnedNet	56000000	usd
CY2022	us-gaap	Insurance Commissions And Fees InsuranceCommissionsAndFees	31000000	usd
CY2022	us-gaap	Contractually Specified Servicing Fees Late Fees And Ancillary Fees Earned In Exchange For Servicing Financial Assets ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets	3000000	usd
CY2022	us-gaap	Net Investment Income NetInvestmentIncome	17000000	usd
CY2022	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	31000000	usd
CY2022	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	129000000	usd
CY2022	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	81000000	usd
CY2022	ambc	Other Income Items OtherIncomeItems	31000000	usd
CY2022	us-gaap	Gain Loss Related To Litigation Settlement GainLossRelatedToLitigationSettlement	126000000	usd
CY2022	us-gaap	Revenues Revenues	505000000	usd
CY2022	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	-396000000	usd
CY2022	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	3000000	usd
CY2022	us-gaap	Insurance Commissions InsuranceCommissions	18000000	usd
CY2022	us-gaap	Operating Expenses OperatingExpenses	139000000	usd
CY2022	us-gaap	Depreciation Depreciation	2000000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	47000000	usd
CY2022	us-gaap	Interest Expense InterestExpense	168000000	usd
CY2022	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	-20000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	525000000	usd
CY2022Q4	us-gaap	Assets Assets	7973000000	usd
CY2021	us-gaap	Premiums Earned Net PremiumsEarnedNet	47000000	usd
CY2021	us-gaap	Insurance Commissions And Fees InsuranceCommissionsAndFees	26000000	usd
CY2021	us-gaap	Contractually Specified Servicing Fees Late Fees And Ancillary Fees Earned In Exchange For Servicing Financial Assets ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets	0	usd
CY2021	us-gaap	Net Investment Income NetInvestmentIncome	139000000	usd
CY2021	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	7000000	usd
CY2021	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	22000000	usd
CY2021	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	33000000	usd
CY2021	ambc	Other Income Items OtherIncomeItems	8000000	usd
CY2021	us-gaap	Gain Loss Related To Litigation Settlement GainLossRelatedToLitigationSettlement	0	usd
CY2021	us-gaap	Revenues Revenues	282000000	usd
CY2021	us-gaap	Incurred Claims Financial Guarantee Insurance Contracts IncurredClaimsFinancialGuaranteeInsuranceContracts	-88000000	usd
CY2021	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	1000000	usd
CY2021	us-gaap	Insurance Commissions InsuranceCommissions	15000000	usd
CY2021	us-gaap	Operating Expenses OperatingExpenses	110000000	usd
CY2021	us-gaap	Depreciation Depreciation	2000000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	55000000	usd
CY2021	us-gaap	Interest Expense InterestExpense	187000000	usd
CY2021	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	281000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	2000000	usd
CY2021Q4	us-gaap	Assets Assets	12303000000	usd
CY2022	ambc	Business Combination Goodwill Expected Tax Deductible Amount Amortization Period BusinessCombinationGoodwillExpectedTaxDeductibleAmountAmortizationPeriod	P15Y
CY2020	ambc	Business Combination Goodwill Expected Tax Deductible Amount Amortization Period BusinessCombinationGoodwillExpectedTaxDeductibleAmountAmortizationPeriod	P15Y
CY2022Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	2041000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	31000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	106000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Current AvailableForSaleSecuritiesCurrent	1966000000	usd
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
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	606000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	605000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	456000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	427000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	317000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	277000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	51000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	43000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	1429000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	1353000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2041000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1966000000	usd
CY2022Q4	ambc	Debt Securities Available For Sale Continuous Unrealized Loss Position DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition	869000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	53000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	400000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	53000000	usd
CY2022Q4	ambc	Debt Securities Available For Sale Unrealized Loss Position Including Pledged Securities DebtSecuritiesAvailableForSaleUnrealizedLossPositionIncludingPledgedSecurities	1269000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	106000000	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	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	ambc	Debt Securities Accumulated Gross Unrealized Loss Before Tax Included Pledged Securities DebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxIncludedPledgedSecurities	16000000	usd
CY2022Q4	ambc	Average Percentage Of Unrealized Loss Versus Amortized Cost For Investment Grade Securities AveragePercentageOfUnrealizedLossVersusAmortizedCostForInvestmentGradeSecurities	0.10
CY2022Q4	ambc	Average Percentage Of Unrealized Loss Versus Amortized Cost For Below Investment Grade Securities AveragePercentageOfUnrealizedLossVersusAmortizedCostForBelowInvestmentGradeSecurities	0.08
CY2021	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	78000000	usd
CY2020	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	103000000	usd
CY2022	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	usd
CY2021	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	usd
CY2020	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	usd
CY2022	us-gaap	Interest And Dividend Income Securities Available For Sale InterestAndDividendIncomeSecuritiesAvailableForSale	66000000	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
CY2022	us-gaap	Net Investment Income NetInvestmentIncome	17000000	usd
CY2021	us-gaap	Net Investment Income NetInvestmentIncome	139000000	usd
CY2020	us-gaap	Net Investment Income NetInvestmentIncome	122000000	usd
CY2022	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	36000000	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
CY2022	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	18000000	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
CY2022	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 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
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	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
CY2022	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	31000000	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
CY2022Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	usd
CY2022Q4	ambc	Fair Value Of Securities Deposited With Governmental Authorities FairValueOfSecuritiesDepositedWithGovernmentalAuthorities	23000000	usd
CY2021Q4	ambc	Fair Value Of Securities Deposited With Governmental Authorities FairValueOfSecuritiesDepositedWithGovernmentalAuthorities	17000000	usd
CY2022Q4	ambc	Fair Valueof Securities Depositedin Connectionwtih Letterof Credit FairValueofSecuritiesDepositedinConnectionwtihLetterofCredit	1000000	usd
CY2021Q4	ambc	Fair Value Ol Securities Held By Ambac Uk Where Capital Stock Of Auk Is Pledged As Collateral For Sitka Aac Note FairValueOlSecuritiesHeldByAmbacUKWhereCapitalStockOfAUKIsPledgedAsCollateralForSitkaAACNote	669000000	usd
CY2022Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	12000000	usd
CY2021Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	8000000	usd
CY2022	us-gaap	Net Realized Or Unrealized Gain Loss On Trading Securities NetRealizedOrUnrealizedGainLossOnTradingSecurities	-48000000	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
CY2022	us-gaap	Trading Securities Realized Gain Loss TradingSecuritiesRealizedGainLoss	-26000000	usd
CY2021	us-gaap	Trading Securities Realized Gain Loss TradingSecuritiesRealizedGainLoss	1000000	usd
CY2020	us-gaap	Trading Securities Realized Gain Loss TradingSecuritiesRealizedGainLoss	-18000000	usd
CY2022Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	12000000	usd
CY2021Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	8000000	usd
CY2022Q4	ambc	Fair Value Yield Rate FairValueYieldRate	0.113
CY2021Q4	ambc	Fair Value Yield Rate FairValueYieldRate	0.116
CY2022	ambc	Fair Value Financial Assets And Liabilities Transfers In Or Out Of Level3 FairValueFinancialAssetsAndLiabilitiesTransfersInOrOutOfLevel3	0
CY2022Q4	ambc	Financial Guarantee Gross Outstanding Principal FinancialGuaranteeGrossOutstandingPrincipal	27551000000	usd
CY2021Q4	ambc	Financial Guarantee Gross Outstanding Principal FinancialGuaranteeGrossOutstandingPrincipal	34122000000	usd
CY2022Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	22613000000	usd
CY2021Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	28020000000	usd
CY2022Q4	ambc	Financial Guarantee Outstanding Principal Ceded To Third Parties FinancialGuaranteeOutstandingPrincipalCededToThirdParties	4938000000	usd
CY2022Q4	ambc	Amount Of Insured Par Outstanding Ceded To Reinsurer AmountOfInsuredParOutstandingCededToReinsurer	2187000000	usd
CY2022	ambc	Ceded Principal Outstanding Major Reinsurer Percentage CededPrincipalOutstandingMajorReinsurerPercentage	0.079
CY2022Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	22613000000	usd
CY2021Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	28020000000	usd
CY2022Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	22613000000	usd
CY2021Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	28020000000	usd
CY2022Q4	ambc	Financial Guarantee Gross Outstanding Principal And Interest FinancialGuaranteeGrossOutstandingPrincipalAndInterest	44734000000	usd
CY2021Q4	ambc	Financial Guarantee Gross Outstanding Principal And Interest FinancialGuaranteeGrossOutstandingPrincipalAndInterest	54272000000	usd
CY2022Q4	ambc	Net Financial Guarantee Principal And Interest In Force NetFinancialGuaranteePrincipalAndInterestInForce	34975000000	usd
CY2021Q4	ambc	Net Financial Guarantee Principal And Interest In Force NetFinancialGuaranteePrincipalAndInterestInForce	42653000000	usd
CY2022	ambc	Percentage Of Highest Single Insured Risk Of Aggregate Net Par Amount Guaranteed PercentageOfHighestSingleInsuredRiskOfAggregateNetParAmountGuaranteed	0.036
CY2022	us-gaap	Direct Premiums Written DirectPremiumsWritten	127000000	usd
CY2022	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	0	usd
CY2022	us-gaap	Ceded Premiums Written CededPremiumsWritten	104000000	usd
CY2022	us-gaap	Premiums Written Net PremiumsWrittenNet	23000000	usd
CY2022	us-gaap	Direct Premiums Earned DirectPremiumsEarned	126000000	usd
CY2022	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	0	usd
CY2022	us-gaap	Ceded Premiums Earned CededPremiumsEarned	69000000	usd
CY2022	us-gaap	Premiums Earned Net PremiumsEarnedNet	56000000	usd
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
CY2022	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	8000000	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
CY2022	us-gaap	Premiums Earned Net Financial Guarantee Insurance Contracts PremiumsEarnedNetFinancialGuaranteeInsuranceContracts	56000000	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
CY2022Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	269000000	usd
CY2021Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	323000000	usd
CY2022Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	259000000	usd
CY2021Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	329000000	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
CY2022	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-4000000	usd
CY2021	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-6000000	usd
CY2022	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	0	usd
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	-2000000	usd
CY2022	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	0	usd
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	0	usd
CY2022Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	5000000	usd
CY2021Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	9000000	usd
CY2022Q4	ambc	Past Due Premiums PastDuePremiums	0	usd
CY2021Q4	ambc	Past Due Premiums PastDuePremiums	0	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
CY2022	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived	-36000000	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
CY2022	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-31000000	usd
CY2021	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-27000000	usd
CY2020	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-6000000	usd
CY2022	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable	8000000	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
CY2022	us-gaap	Allowance For Doubtful Accounts Receivable Period Increase Decrease AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease	4000000	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
CY2022	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments	-12000000	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
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	254000000	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
CY2022	ambc	Financial Guarantee Insurance Contracts Premiums Receivable Increase Decrease Foreign Exchange FinancialGuaranteeInsuranceContractsPremiumsReceivableIncreaseDecreaseForeignExchange	-13000000	usd
CY2021	ambc	Financial Guarantee Insurance Contracts Premiums Receivable Increase Decrease Foreign Exchange FinancialGuaranteeInsuranceContractsPremiumsReceivableIncreaseDecreaseForeignExchange	-2000000	usd
CY2020	ambc	Financial Guarantee Insurance Contracts Premiums Receivable Increase Decrease Foreign Exchange FinancialGuaranteeInsuranceContractsPremiumsReceivableIncreaseDecreaseForeignExchange	4000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During First Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFirstQuarterFollowingBalanceSheetDate	8000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During First Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFirstQuarterFollowingBalanceSheetDate	5000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Second Quarter Following The Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringSecondQuarterFollowingTheBalanceSheetDate	7000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Second Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringSecondQuarterFollowingBalanceSheetDate	5000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Third Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringThirdQuarterFollowingBalanceSheetDate	7000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Third Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringThirdQuarterFollowingBalanceSheetDate	5000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Fourth Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFourthQuarterFollowingBalanceSheetDate	5000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Fourth Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFourthQuarterFollowingBalanceSheetDate	5000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than One And Within Two Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanOneAndWithinTwoYearsFromBalanceSheetDate	26000000	usd
CY2022Q4	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	19000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Two And Within Three Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanTwoAndWithinThreeYearsFromBalanceSheetDate	25000000	usd
CY2022Q4	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	18000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Three And Within Four Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanThreeAndWithinFourYearsFromBalanceSheetDate	24000000	usd
CY2022Q4	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	18000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Four And Within Five Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate	23000000	usd
CY2022Q4	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	17000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Five And Within10 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFiveAndWithin10YearsFromBalanceSheetDate	95000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Five And Within10 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFiveAndWithin10YearsFromBalanceSheetDate	70000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than10 And Within15 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan10AndWithin15YearsFromBalanceSheetDate	59000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than10 And Within15 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan10AndWithin15YearsFromBalanceSheetDate	42000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than15 And Within20 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan15AndWithin20YearsFromBalanceSheetDate	27000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than15 And Within20 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan15AndWithin20YearsFromBalanceSheetDate	17000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than20 And Within25 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan20AndWithin25YearsFromBalanceSheetDate	13000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than20 And Within25 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan20AndWithin25YearsFromBalanceSheetDate	8000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than25 And Within30 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan25AndWithin30YearsFromBalanceSheetDate	4000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than25 And Within30 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan25AndWithin30YearsFromBalanceSheetDate	2000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than30 And Within35 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan30AndWithin35YearsFromBalanceSheetDate	0	usd
CY2022Q4	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
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Premium Expected To Be Collected FinancialGuaranteeInsuranceContractsPremiumReceivablePremiumExpectedToBeCollected	322000000	usd
CY2022Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognized	231000000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	805000000	usd
CY2022Q4	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	271000000	usd
CY2022Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	534000000	usd
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1570000000	usd
CY2021Q4	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	2092000000	usd
CY2021Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	-522000000	usd
CY2022	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:3pt;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%">2022</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2021</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 5.5pt;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:700;line-height:100%">Beginning gross loss and loss adjustment expense reserves</span></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%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(522)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</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%">(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"/></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%">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:#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%">33 </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"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 5.5pt;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%">Beginning balance of net loss and loss adjustment expense reserves</span></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%">(578)</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%">(508)</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%">4</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%">— </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"/></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%">(401)</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%">(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"/></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%">(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 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%">(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"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 5.5pt;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:700;line-height:100%">Loss and loss adjustment expenses (recovered) paid:</span></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%">7</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%">— </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%">(1,867)</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%">59 </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"/></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%">(1,860)</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%">59 </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"/></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%">(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%">— </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"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 5.5pt;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%">Ending net loss and loss adjustment expense reserves</span></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%">883</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%">(578)</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"/></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><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:#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%">(464)</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%">— </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">(4)</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%">115</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%">55 </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"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 5.5pt;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:700;line-height:100%">Ending gross loss and loss adjustment expense reserves</span></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%">534</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-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%">(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"/></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 $(41), $5 and $(7) for the years ended December 31, 2022, 2021 and 2020, 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 representations and warranties ("R&W's") by transaction sponsors within losses and loss expenses (benefit) for the Legacy Financial Guarantee segment. The losses and loss expense (benefit) incurred associated with changes in estimated R&W's for the year ended December 31, 2022, 2021 and 2020 was $(123), $20 and $(23), </span></div><div style="margin-bottom:3pt;margin-top:3pt;padding-left:18pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">respectively. Refer to Note 1. Background and Business Description to the Consolidated Financial Statements in this Annual Report on Form 10-K for details of the RMBS litigation settlements reached in October and December 2022. </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%">(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">In connection with the Puerto Rico restructuring, three new trusts were established for the year ended December 31, 2022. These trusts were consolidated by Ambac as further discussed in Note 12. Variable Interest Entities.</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%">(4)</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 adjustment expenses. Additionally, the Balance Sheet line "Reinsurance recoverable on paid and unpaid losses" includes reinsurance recoverables (payables) of $0, $0 and $0 as of December 31, 2022, 2021 and 2020, respectively, related to previously presented loss and loss adjustment expenses and subrogation.</span></div>
CY2021Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	-522000000	usd
CY2020Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	-397000000	usd
CY2019Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	-482000000	usd
CY2021Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	55000000	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
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	-578000000	usd
CY2020Q4	ambc	Liability For Unpaid Claims And Claims Adjustment Expense Net Of Vie Consolidation LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNetOfVIEConsolidation	-430000000	usd
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	-508000000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	4000000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	0	usd
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	15000000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-401000000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-89000000	usd
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	210000000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	-397000000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	-88000000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	225000000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	7000000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	0	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1000000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	-1867000000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	59000000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	148000000	usd
CY2022	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	-1860000000	usd
CY2021	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	59000000	usd
CY2020	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	149000000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	-2000000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	0	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	2000000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	883000000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	-578000000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	-430000000	usd
CY2022Q4	ambc	Impactof Vie Consolidationon Gross Lossand Loss Reserves ImpactofVIEConsolidationonGrossLossandLossReserves	-464000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	115000000	usd
CY2021Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	55000000	usd
CY2020Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	33000000	usd
CY2022Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	534000000	usd
CY2021Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	-522000000	usd
CY2020Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	-397000000	usd
CY2022	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	41000000	usd
CY2021	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	-5000000	usd
CY2020	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	7000000	usd
CY2022	ambc	Net Incurred Rmbs Subrogation Recoveries NetIncurredRMBSSubrogationRecoveries	123000000	usd
CY2021	ambc	Net Incurred Rmbs Subrogation Recoveries NetIncurredRMBSSubrogationRecoveries	-20000000	usd
CY2020	ambc	Net Incurred Rmbs Subrogation Recoveries NetIncurredRMBSSubrogationRecoveries	23000000	usd
CY2021Q4	ambc	Ceded Loss And Loss Expenses Paid Not Yet Recovered CededLossAndLossExpensesPaidNotYetRecovered	0	usd
CY2020Q4	ambc	Ceded Loss And Loss Expenses Paid Not Yet Recovered CededLossAndLossExpensesPaidNotYetRecovered	0	usd
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Number Of Contracts Issued And Outstanding ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNumberOfContractsIssuedAndOutstanding	162	policies
CY2022	us-gaap	Insured Financial Obligations With Credit Deterioration Remaining Weighted Average Contract Period InsuredFinancialObligationsWithCreditDeteriorationRemainingWeightedAverageContractPeriod	P13Y
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Principal ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingPrincipal	4047000000	usd
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Interest ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingInterest	1750000000	usd
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstanding	5797000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Gross Undiscounted Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossUndiscountedClaimLiability	-1279000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Discount On Gross Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationDiscountOnGrossClaimLiability	-496000000	usd
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Gross Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossClaimLiability	-783000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedRmbsSubrogation	140000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnRmbsSubrogation	0	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation	140000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedOtherSubrogation	233000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnOtherSubrogation	54000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityOtherSubrogation	179000000	usd
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Net Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNetClaimLiability	-464000000	usd
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Unearned Premium Revenue ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionUnearnedPremiumRevenue	-28000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Loss Adjustment Expenses Reserve ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationLossAdjustmentExpensesReserve	8000000	usd
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Reinsurance Recoverable ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionReinsuranceRecoverable	33000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Number Of Contracts Issued And Outstanding ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNumberOfContractsIssuedAndOutstanding	205	policies
CY2021	us-gaap	Insured Financial Obligations With Credit Deterioration Remaining Weighted Average Contract Period InsuredFinancialObligationsWithCreditDeteriorationRemainingWeightedAverageContractPeriod	P14Y
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Principal ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingPrincipal	6302000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Interest ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingInterest	2984000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstanding	9286000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Gross Undiscounted Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossUndiscountedClaimLiability	-2095000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Discount On Gross Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationDiscountOnGrossClaimLiability	-303000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Gross Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossClaimLiability	-1792000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedRmbsSubrogation	1737000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnRmbsSubrogation	7000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation	1730000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedOtherSubrogation	633000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnOtherSubrogation	28000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityOtherSubrogation	605000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Net Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNetClaimLiability	543000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Unearned Premium Revenue ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionUnearnedPremiumRevenue	-56000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Loss Adjustment Expenses Reserve ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationLossAdjustmentExpensesReserve	45000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionClaimLiability	-554000000	usd
CY2021Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Reinsurance Recoverable ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionReinsuranceRecoverable	23000000	usd
CY2021Q4	ambc	Loss Reserves Ceded To Reinsurers LossReservesCededToReinsurers	24000000	usd
CY2021Q4	ambc	Ceded Loss And Loss Expenses Paid Not Yet Recovered CededLossAndLossExpensesPaidNotYetRecovered	0	usd
CY2022Q4	ambc	Public Finance Puerto Rico Net Par Outstanding PublicFinancePuertoRicoNetParOutstanding	244000000	usd
CY2022Q4	ambc	Cash Shared By Prhta Creditors Under The Prhtaccdapsa CashSharedByPRHTACreditorsUnderThePRHTACCDAPSA	389000000	usd
CY2022Q3	ambc	Percent Of Creditor Clawback Of Sut Subject To Lifetime Cap PercentOfCreditorClawbackOfSUTSubjectToLifetimeCap	0.69
CY2022Q3	ambc	Lifetime Cap Of Creditor Clawback Of Sut LifetimeCapOfCreditorClawbackOfSUT	3698000000	usd
CY2022Q3	ambc	New Prhta Bonds To Be Issued NewPRHTABondsToBeIssued	1245000000	usd
CY2022Q3	ambc	New Prhta Bonds To Be Issued NewPRHTABondsToBeIssued	1245000000	usd
CY2022Q4	ambc	Amount Of Prhta Insured Exposure Fully Satisfied AmountOfPRHTAInsuredExposureFullySatisfied	4000000	usd
CY2022Q4	ambc	Percent Of Prhta Net Par Exposure Fully Satisfied PercentOfPRHTANetParExposureFullySatisfied	0.21
CY2022Q4	ambc	Amount Of Prhta Net Par Exposure Fully Satisfied AmountOfPRHTANetParExposureFullySatisfied	83000000	usd
CY2022Q4	ambc	Amount Of Net Par Exposure Put In Trust And Consolidated By Ambac AmountOfNetParExposurePutInTrustAndConsolidatedByAmbac	312000000	usd
CY2022Q4	ambc	Amount Of Net Par Exposure Put In Trust And Consolidated By Ambac AmountOfNetParExposurePutInTrustAndConsolidatedByAmbac	178000000	usd
CY2022Q1	ambc	Aac Insured Gopba Bonds Satisfied Or Eliminated AACInsuredGOPBABondsSatisfiedOrEliminated	94	usd
CY2022Q1	ambc	Percent Of Par Of Aa Cs Outstanding Aac Insured Prifa Eliminated PercentOfParOfAACsOutstandingAACInsuredPRIFAEliminated	0.39
CY2022Q1	ambc	Percent Of Par Of Aa Cs Outstanding Aac Insured Ccda Eliminated PercentOfParOfAACsOutstandingAACInsuredCCDAEliminated	0.19
CY2022Q1	ambc	Amount Of Aac Insured Par Of Prifa And Ccda Eliminated AmountOfAACInsuredParOfPRIFAAndCCDAEliminated	172000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation	140000000	usd
CY2022Q4	ambc	Balance Of Rmbs Subrogation Recoveries Net Of Reinsurance BalanceOfRmbsSubrogationRecoveriesNetOfReinsurance	-140000000	usd
CY2021Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation	1730000000	usd
CY2021Q4	ambc	Balance Of Rmbs Subrogation Recoveries Net Of Reinsurance BalanceOfRmbsSubrogationRecoveriesNetOfReinsurance	-1704000000	usd
CY2022Q4	ambc	Deferred Ceded Premiums And Reinsurance Recoverables DeferredCededPremiumsAndReinsuranceRecoverables	239000000	usd
CY2022Q4	us-gaap	Reinsurance Payable ReinsurancePayable	39000000	usd
CY2022Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	116000000	usd
CY2022Q4	ambc	Number Of Reinsurers Covering Majority NumberOfReinsurersCoveringMajority	3
CY2022Q4	ambc	Percentage Of Ceded Reinsurance Recoverable Represented By Top Three PercentageOfCededReinsuranceRecoverableRepresentedByTopThree	0.842
CY2022Q4	ambc	Reinsurance Recoverable Gross All Other ReinsuranceRecoverableGrossAllOther	18000000	usd
CY2022Q4	ambc	Unsecured Reinsurance Recoverable All Other UnsecuredReinsuranceRecoverableAllOther	7000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	115000000	usd
CY2022Q4	ambc	Unsecured Reinsurance Recoverables UnsecuredReinsuranceRecoverables	60000000	usd
CY2022Q4	ambc	Reinsurance Recoverable Credit Exposure ReinsuranceRecoverableCreditExposure	60000000	usd
CY2021Q4	ambc	Reinsurance Recoverable Credit Exposure ReinsuranceRecoverableCreditExposure	32000000	usd
CY2022Q4	ambc	Uncollateralized Credit Exposure Supoorted By Unlimited Uncapped Indemnity UncollateralizedCreditExposureSupoortedByUnlimitedUncappedIndemnity	45000000	usd
CY2021Q4	ambc	Uncollateralized Credit Exposure Supoorted By Unlimited Uncapped Indemnity UncollateralizedCreditExposureSupoortedByUnlimitedUncappedIndemnity	30000000	usd
CY2022Q4	ambc	Average Annual Rate Of Return AverageAnnualRateOfReturn	0.0322
CY2021Q4	ambc	Average Annual Rate Of Return AverageAnnualRateOfReturn	0.0528
CY2022	ambc	Prescribed Discount Rate Percentage PrescribedDiscountRatePercentage	0.0510
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	28000000	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	0	usd
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CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	38000000	usd
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CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	76000000	usd
CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	0	usd
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CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	0	usd
CY2021Q4	ambc	Derivative Assets Net Amount DerivativeAssetsNetAmount	76000000	usd
CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	95000000	usd
CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	0	usd
CY2021Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	95000000	usd
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CY2022Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	6000000	usd
CY2021Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	13000000	usd
CY2021Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	0	usd
CY2022Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	0	usd
CY2022	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	129000000	usd
CY2021	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	22000000	usd
CY2020	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-50000000	usd
CY2022	ambc	Derivative Gain Losson Derivatives Total Net DerivativeGainLossonDerivativesTotalNet	694000000	usd
CY2021	ambc	Derivative Gain Losson Derivatives Total Net DerivativeGainLossonDerivativesTotalNet	-128000000	usd
CY2020	ambc	Derivative Gain Losson Derivatives Total Net DerivativeGainLossonDerivativesTotalNet	-193000000	usd
CY2022Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	38000000	usd
CY2021Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	93000000	usd
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CY2021Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	109000000	usd
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CY2022Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	326000000	usd
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CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	31000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	29000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	27000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	25000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	23000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	178000000	usd
CY2022	ambc	Variable Interest Entity Changein Fair Valueof Assetsand Liabilities VariableInterestEntityChangeinFairValueofAssetsandLiabilities	0	usd
CY2022Q4	us-gaap	Debt Instrument Interest Rate Effective Percentage DebtInstrumentInterestRateEffectivePercentage	0.070
CY2021	ambc	Variable Interest Entity Changein Fair Valueof Assetsand Liabilities VariableInterestEntityChangeinFairValueofAssetsandLiabilities	4000000	usd
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CY2022	us-gaap	Variable Interest Entity Initial Consolidation Gain Or Loss VariableInterestEntityInitialConsolidationGainOrLoss	37000000	usd
CY2021	us-gaap	Variable Interest Entity Initial Consolidation Gain Or Loss VariableInterestEntityInitialConsolidationGainOrLoss	0	usd
CY2020	us-gaap	Variable Interest Entity Initial Consolidation Gain Or Loss VariableInterestEntityInitialConsolidationGainOrLoss	0	usd
CY2022	us-gaap	Variable Interest Entity Activity Between Vie And Entity Income Or Loss Before Tax VariableInterestEntityActivityBetweenVIEAndEntityIncomeOrLossBeforeTax	21000000	usd
CY2021	us-gaap	Variable Interest Entity Activity Between Vie And Entity Income Or Loss Before Tax VariableInterestEntityActivityBetweenVIEAndEntityIncomeOrLossBeforeTax	7000000	usd
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CY2022	us-gaap	Variable Interest Entity Initial Consolidation Gain Or Loss VariableInterestEntityInitialConsolidationGainOrLoss	37000000	usd
CY2021	ambc	Number Of De Consolidated Variable Interest Entities NumberOfDeConsolidatedVariableInterestEntities	0
CY2020	ambc	Number Of De Consolidated Variable Interest Entities NumberOfDeConsolidatedVariableInterestEntities	0
CY2022	ambc	Number Of De Consolidated Variable Interest Entities NumberOfDeConsolidatedVariableInterestEntities	0
CY2022Q4	us-gaap	Variable Interest Entity Entity Maximum Loss Exposure Amount VariableInterestEntityEntityMaximumLossExposureAmount	21639000000	usd
CY2022Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Assets VariableInterestEntityNonconsolidatedCarryingAmountInsuranceAssets	490000000	usd
CY2022Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Liabilities VariableInterestEntityNonconsolidatedCarryingAmountInsuranceLiabilities	840000000	usd
CY2022Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Derivative Net Assets Or Liabilities VariableInterestEntityNonconsolidatedCarryingAmountDerivativeNetAssetsOrLiabilities	1000000	usd
CY2021Q4	us-gaap	Variable Interest Entity Entity Maximum Loss Exposure Amount VariableInterestEntityEntityMaximumLossExposureAmount	25112000000	usd
CY2021Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Assets VariableInterestEntityNonconsolidatedCarryingAmountInsuranceAssets	2195000000	usd
CY2021Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Liabilities VariableInterestEntityNonconsolidatedCarryingAmountInsuranceLiabilities	1023000000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	665000000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	0	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	41000000	usd
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CY2018Q1	ambc	Tier2 Note Securityin Rmbs Litigation Settlement Proceeds Tier2NoteSecurityinRMBSLitigationSettlementProceeds	1600000000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	31000000	usd
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CY2022Q4	us-gaap	Contract With Customer Receivable After Allowance For Credit Loss ContractWithCustomerReceivableAfterAllowanceForCreditLoss	7000000	usd
CY2021Q4	us-gaap	Contract With Customer Receivable After Allowance For Credit Loss ContractWithCustomerReceivableAfterAllowanceForCreditLoss	2000000	usd
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CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	58000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-296000000	usd
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CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-253000000	usd
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CY2021	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	9000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-21000000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	58000000	usd
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	44973757	shares
CY2022Q4	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	4877617	shares
CY2013Q2	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	16.67
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CY2021	ambc	Warrant Exercised During Period Shares WarrantExercisedDuringPeriodShares	132	shares
CY2020	ambc	Warrant Exercised During Period Shares WarrantExercisedDuringPeriodShares	34	shares
CY2022	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	0	shares
CY2021	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	4	shares
CY2020	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	8	shares
CY2022Q1	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	20000000	usd
CY2022	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	1605316	shares
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	-14200000	usd
CY2022Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	15000000	usd
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CY2021	us-gaap	Net Income Loss NetIncomeLoss	-17000000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-437000000	usd
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CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	525000000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-28000000	usd
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-437000000	usd
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	11.48
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.61
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CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.61
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-9.47
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	45719906	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46535001	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46147062	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46414830	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46535001	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46147062	shares
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	511000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-32000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-441000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	13000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	34000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	1000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	525000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2000000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-440000000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	0	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	2000000	usd
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CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	7000000	usd
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	10000000	usd
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	8000000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6000000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	12000000	usd
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	8000000	usd
CY2022	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-4000000	usd
CY2021	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	6000000	usd
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CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4000000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	6000000	usd
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CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18000000	usd
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CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18000000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3000000	usd
CY2022	ambc	Net Unrealized Losses On Securities Tax Effect NetUnrealizedLossesOnSecuritiesTaxEffect	-47000000	usd
CY2021	ambc	Net Unrealized Losses On Securities Tax Effect NetUnrealizedLossesOnSecuritiesTaxEffect	-3000000	usd
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CY2022	ambc	Change In Retirement Benefits Tax Effect ChangeInRetirementBenefitsTaxEffect	0	usd
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CY2022	ambc	Credit Risk Changes To Fair Value Options Tax Effect CreditRiskChangesToFairValueOptionsTaxEffect	0	usd
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CY2022	ambc	Valuation Allowances And Reserves Charged To Equity ValuationAllowancesAndReservesChargedToEquity	-41000000	usd
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CY2022	us-gaap	Income Tax Effects Allocated Directly To Equity IncomeTaxEffectsAllocatedDirectlyToEquity	-6000000	usd
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CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	110000000	usd
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CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-92000000	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2022	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	1000000	usd
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CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	1.14
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CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0
CY2022	us-gaap	Income Tax Reconciliation Tax Contingencies Foreign IncomeTaxReconciliationTaxContingenciesForeign	4000000	usd
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CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies Foreign EffectiveIncomeTaxRateReconciliationTaxContingenciesForeign	4.48
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CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-1000000	usd
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CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	14000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	7.94
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	0	usd
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$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc

2023 Q1 Form 10-K Financial Statement

#000087450123000040 Filed on March 01, 2023

Income Statement

Balance Sheet

Cashflow Statement

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$AMBC AMBAC FINANCIAL GROUP INC Stock $ambc

2023 Q1 Form 10-K Financial Statement

#000087450123000040 Filed on March 01, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc