$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc

$ambc Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000087450124000040 Filed on February 27, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$103.0M	$78.00M	$269.0M
YoY Change	77.59%	8.33%	-46.73%
Cost Of Revenue	-$1.000M		-$33.00M
YoY Change	-105.56%		-91.67%
Gross Profit	$104.0M		$302.0M
YoY Change	160.0%		-66.48%
Gross Profit Margin	100.97%		112.27%
Selling, General & Admin	$36.00M	$34.00M	$156.0M
YoY Change	0.0%	-33.33%	10.64%
% of Gross Profit	34.62%		51.66%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$1.000M	$9.000M	$2.000M
YoY Change		-35.71%	0.0%
% of Gross Profit	0.96%		0.66%
Operating Expenses	$53.00M	$70.00M	$155.0M
YoY Change	-19.7%	483.33%	11.51%
Operating Profit	$51.00M		$147.0M
YoY Change	-296.15%		-80.71%
Interest Expense	$16.00M	-$18.00M	$64.00M
YoY Change	0.0%	-50.0%	-61.9%
% of Operating Profit	31.37%		43.54%
Other Income/Expense, Net	-$4.000M	-$6.000M	-$11.00M
YoY Change	100.0%	500.0%	266.67%
Pretax Income	$26.00M	-$16.00M	$12.00M
YoY Change	-189.66%	-109.25%	-97.71%
Income Tax	$5.000M	$0.00	$7.000M
% Of Pretax Income	19.23%		58.33%
Net Earnings	$20.00M	-$11.00M	$4.000M
YoY Change	-160.61%	-106.18%	-99.23%
Net Earnings / Revenue	19.42%	-14.1%	1.49%
Basic Earnings Per Share	$0.44		$0.18
Diluted Earnings Per Share	$0.43	-$0.24	$0.18
COMMON SHARES
Basic Shares Outstanding	45.20M shares	45.19M shares	45.64M shares
Diluted Shares Outstanding	46.35M shares		46.54M shares

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments	$2.128B	$2.178B
YoY Change	8.52%	9.06%
Cash & Equivalents	$33.00M	$16.00M	$28.00M
Short-Term Investments	$2.095B	$2.162B
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment			$19.00M
YoY Change			-9.52%
Goodwill	$70.00M	$70.00M
YoY Change	14.75%	14.75%
Intangibles	$293.0M	$307.0M
YoY Change	-8.72%	-5.83%
Long-Term Investments	$6.448B	$6.494B	$6.494B
YoY Change	-0.56%	1.64%	1.64%
Other Assets	$264.0M	$246.0M	$246.0M
YoY Change	3.13%	1347.06%	1347.06%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$8.429B	$8.428B	$8.428B
YoY Change	2.56%	5.71%	5.71%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$487.0M	$475.0M	$497.0M
YoY Change	11.19%	5.09%	9.96%
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	$487.0M	$475.0M	$497.0M
YoY Change	11.19%	5.09%	9.96%
LONG-TERM LIABILITIES
Long-Term Debt	$3.437B	$3.475B	$3.475B
YoY Change	-3.37%	-7.23%	-7.23%
Other Long-Term Liabilities	$1.680B	$1.642B	$1.620B
YoY Change	3.7%	32.97%	31.19%
Total Long-Term Liabilities	$5.117B	$5.117B	$5.095B
YoY Change	-1.16%	2.73%	2.29%
TOTAL LIABILITIES
Total Short-Term Liabilities	$487.0M	$475.0M	$497.0M
Total Long-Term Liabilities	$5.117B	$5.117B	$5.095B
Total Liabilities	$6.993B	$6.997B	$7.067B
YoY Change	1.47%	5.27%	5.13%
SHAREHOLDERS EQUITY
Retained Earnings	$1.266B	$1.246B
YoY Change	4.98%	0.08%
Common Stock	$0.00	$0.00
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$17.00M	$17.00M
YoY Change	21.43%	13.33%
Treasury Stock Shares
Shareholders Equity	$1.365B	$1.362B	$1.361B
YoY Change
Total Liabilities & Shareholders Equity	$8.429B	$8.428B	$8.428B
YoY Change	2.56%	5.71%	5.71%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$20.00M	-$11.00M	$4.000M
YoY Change	-160.61%	-106.18%	-99.23%
Depreciation, Depletion And Amortization	$1.000M	$9.000M	$2.000M
YoY Change		-35.71%	0.0%
Cash From Operating Activities	$18.00M	$88.00M	$200.0M
YoY Change	-76.62%	-93.11%	-85.02%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions			$7.000M
YoY Change			-138.89%
Other Investing Activities	$0.00	-$86.00M	-$6.000M
YoY Change	-100.0%	-119.95%	-33.33%
Cash From Investing Activities	$51.00M	-$86.00M	$435.0M
YoY Change	-88.44%	-119.95%	-49.77%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$5.000M
YoY Change			-135.21%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-$47.00M	-31.00M	-$423.0M
YoY Change	-82.97%	-98.16%	-80.44%
NET CHANGE
Cash From Operating Activities	$18.00M	88.00M	$200.0M
Cash From Investing Activities	$51.00M	-86.00M	$435.0M
Cash From Financing Activities	-$47.00M	-31.00M	-$423.0M
Net Change In Cash	$21.00M	-29.00M	$213.0M
YoY Change	-91.36%	-220.83%	460.53%
FREE CASH FLOW
Cash From Operating Activities	$18.00M	$88.00M	$200.0M
Capital Expenditures
Free Cash Flow
YoY Change

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2023	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2023	dei	Entity Central Index Key EntityCentralIndexKey	0000874501
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Annual Report DocumentAnnualReport	true
CY2023	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2023	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2023	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2023	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2023	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2023	dei	Entity Small Business EntitySmallBusiness	false
CY2023	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2023	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2023	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2023	dei	Entity Shell Company EntityShellCompany	false
CY2023Q2	dei	Entity Public Float EntityPublicFloat	623109150	usd
CY2024Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	45195370	shares
CY2013Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY1991Q2	dei	Entity Incorporation Date Of Incorporation EntityIncorporationDateOfIncorporation	1991-04-29
CY2023Q4	ambc	Number Of Admitted Carriers Owned NumberOfAdmittedCarriersOwned	5	usd
CY2023	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3
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CY2023	dei	Auditor Name AuditorName	KPMG LLP
CY2023	dei	Auditor Location AuditorLocation	New York, NY
CY2023	dei	Auditor Firm AuditorFirmId	185
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1710000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1395000000	usd
CY2023Q4	us-gaap	Debt Securities Trading And Available For Sale DebtSecuritiesTradingAndAvailableForSale	27000000	usd
CY2022Q4	us-gaap	Debt Securities Trading And Available For Sale DebtSecuritiesTradingAndAvailableForSale	59000000	usd
CY2023Q4	ambc	Short Term Investments Amortized Cost ShortTermInvestmentsAmortizedCost	426000000	usd
CY2022Q4	ambc	Short Term Investments Amortized Cost ShortTermInvestmentsAmortizedCost	507000000	usd
CY2023Q4	us-gaap	Short Term Investments ShortTermInvestments	426000000	usd
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CY2023Q4	us-gaap	Other Investments OtherInvestments	475000000	usd
CY2022Q4	us-gaap	Other Investments OtherInvestments	568000000	usd
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CY2023Q4	us-gaap	Investments Investments	2664000000	usd
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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
CY2023	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition After Tax OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionReclassificationAdjustmentFromAociForDerecognitionAfterTax	0	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
CY2023	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-2000000	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
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	93000000	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
CY2023	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	98000000	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
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-1000000	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
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CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	96000000	usd
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CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-38000000	usd
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.18
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	11.48
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.61
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.18
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	11.31
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.61
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	45636649	shares
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
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46540706	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
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
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CY2021	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	-12000000	usd
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CY2022	ambc	Comprehensive Income Loss Net Of Tax Including Portion Attributable To Noncontrolling Interest Total Excluding Gain On Amps Repurchase ComprehensiveIncomeLossNetOfTaxIncludingPortionAttributableToNoncontrollingInterestTotalExcludingGainOnAMPSRepurchase	211000000	usd
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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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CY2023	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-5000000	usd
CY2023	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	5000000	usd
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CY2023	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	15000000	usd
CY2022	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	11000000	usd
CY2021	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	13000000	usd
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CY2023	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	-30000000	usd
CY2022	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	-58000000	usd
CY2021	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	-82000000	usd
CY2023	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	-130000000	usd
CY2021	ambc	Proceeds From Financial Guaranty Variable Interest Entity Assets ProceedsFromFinancialGuarantyVariableInterestEntityAssets	171000000	usd
CY2023	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	7000000	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
CY2023	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	52000000	usd
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CY2023	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-1000000	usd
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CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1335000000	usd
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CY2023	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	140000000	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	523000000	usd
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	236000000	usd
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CY2023	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	-42000000	usd
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CY2023	ambc	Proceeds From Financial Guaranty Variable Interest Entity Assets ProceedsFromFinancialGuarantyVariableInterestEntityAssets	199000000	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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CY2023	ambc	Paydownof Financial Guaranty Variable Interest Entity Liabilities PaydownofFinancialGuarantyVariableInterestEntityLiabilities	315000000	usd
CY2022	ambc	Paydownof Financial Guaranty Variable Interest Entity Liabilities PaydownofFinancialGuarantyVariableInterestEntityLiabilities	591000000	usd
CY2021	ambc	Paydownof Financial Guaranty Variable Interest Entity Liabilities PaydownofFinancialGuarantyVariableInterestEntityLiabilities	170000000	usd
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CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2163000000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-657000000	usd
CY2023	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1000000	usd
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CY2021	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	0	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	213000000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	38000000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-12000000	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
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	274000000	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
CY1991Q2	dei	Entity Incorporation Date Of Incorporation EntityIncorporationDateOfIncorporation	1991-04-29
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CY2023	us-gaap	Temporary Equity Accretion To Redemption Value Adjustment TemporaryEquityAccretionToRedemptionValueAdjustment	-5000000	usd
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CY2023Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	17000000	usd
CY2022Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	20000000	usd
CY2023	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:10pt;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". </span></div><div style="margin-bottom:9pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">The CECL impact on available-for-sale debt securities is discussed in the Investments sub-section below. </span></div><div style="margin-bottom:9pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">The CECL impact on amortized cost assets, including contract assets and receivables accounted for under the ASC 606 revenue recognition standard, is addressed in the Premiums, Reinsurance Recoverables, Loans and Revenue Recognition 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.
CY2023Q4	ambc	Cecl Securities Factor For Consideration CECLSecuritiesFactorForConsideration	0.20
CY2023Q4	ambc	Accrued Investment Interest Receivable Write Off Period In Days AccruedInvestmentInterestReceivableWriteOffPeriodInDays	90
CY2023Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	14000000	usd
CY2022Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	10000000	usd
CY2023Q4	ambc	Estimated Future Premium Payments Weighted Average Discounted Rate EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate	0.032
CY2022Q4	ambc	Estimated Future Premium Payments Weighted Average Discounted Rate EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate	0.030
CY2023	us-gaap	Financial Guarantee Insurance Contracts Premium Received Over Contract Period Premium Receivable Weighted Average Collection Period1 FinancialGuaranteeInsuranceContractsPremiumReceivedOverContractPeriodPremiumReceivableWeightedAverageCollectionPeriod1	P7Y8M12D
CY2022	us-gaap	Financial Guarantee Insurance Contracts Premium Received Over Contract Period Premium Receivable Weighted Average Collection Period1 FinancialGuaranteeInsuranceContractsPremiumReceivedOverContractPeriodPremiumReceivableWeightedAverageCollectionPeriod1	P8Y
CY2023Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	usd
CY2023	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	usd
CY2023	us-gaap	Impairment Of Intangible Assets Indefinitelived Excluding Goodwill ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	0	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
CY2022Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	20000000	usd
CY2021Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	18000000	usd
CY2023Q4	us-gaap	Business Combination Acquisition Of Less Than100 Percent Noncontrolling Interest Fair Value BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue	2000000	usd
CY2022Q4	us-gaap	Business Combination Acquisition Of Less Than100 Percent Noncontrolling Interest Fair Value BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue	5000000	usd
CY2023	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	1000000	usd
CY2023	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-3000000	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
CY2023	us-gaap	Income Taxes Paid IncomeTaxesPaid	11000000	usd
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	6000000	usd
CY2023	ambc	Non Cash Exchange Of Puerto Rico Bonds NonCashExchangeOfPuertoRicoBonds	0	usd
CY2022	ambc	Non Cash Exchange Of Puerto Rico Bonds NonCashExchangeOfPuertoRicoBonds	185000000	usd
CY2021	ambc	Non Cash Exchange Of Puerto Rico Bonds NonCashExchangeOfPuertoRicoBonds	0	usd
CY2023	ambc	Decrease In Long Term Debt As A Result Of Surplus Notes Exchanges DecreaseInLongTermDebtAsAResultOfSurplusNotesExchanges	0	usd
CY2022	ambc	Decrease In Long Term Debt As A Result Of Surplus Notes Exchanges DecreaseInLongTermDebtAsAResultOfSurplusNotesExchanges	0	usd
CY2021	ambc	Decrease In Long Term Debt As A Result Of Surplus Notes Exchanges DecreaseInLongTermDebtAsAResultOfSurplusNotesExchanges	71000000	usd
CY2023	ambc	Securities Acquired In Transactions Related To Puerto Rico Restructurings SecuritiesAcquiredInTransactionsRelatedToPuertoRicoRestructurings	-1000000	usd
CY2022	ambc	Securities Acquired In Transactions Related To Puerto Rico Restructurings SecuritiesAcquiredInTransactionsRelatedToPuertoRicoRestructurings	508000000	usd
CY2021	ambc	Securities Acquired In Transactions Related To Puerto Rico Restructurings SecuritiesAcquiredInTransactionsRelatedToPuertoRicoRestructurings	0	usd
CY2023	ambc	Loans Acquired Through Financial Guarantee Subrogation LoansAcquiredThroughFinancialGuaranteeSubrogation	0	usd
CY2022	ambc	Loans Acquired Through Financial Guarantee Subrogation LoansAcquiredThroughFinancialGuaranteeSubrogation	20000000	usd
CY2021	ambc	Loans Acquired Through Financial Guarantee Subrogation LoansAcquiredThroughFinancialGuaranteeSubrogation	0	usd
CY2023	ambc	Vie Long Term Debt Issued Related To Puerto Rico Restructurings VIELongTermDebtIssuedRelatedToPuertoRicoRestructurings	0	usd
CY2022	ambc	Vie Long Term Debt Issued Related To Puerto Rico Restructurings VIELongTermDebtIssuedRelatedToPuertoRicoRestructurings	583000000	usd
CY2021	ambc	Vie Long Term Debt Issued Related To Puerto Rico Restructurings VIELongTermDebtIssuedRelatedToPuertoRicoRestructurings	0	usd
CY2023	ambc	Decrease In Vie Loans As A Result Of De Consolidations DecreaseInVIELoansAsAResultOfDeConsolidations	133000000	usd
CY2022	ambc	Decrease In Vie Loans As A Result Of De Consolidations DecreaseInVIELoansAsAResultOfDeConsolidations	0	usd
CY2021	ambc	Decrease In Vie Loans As A Result Of De Consolidations DecreaseInVIELoansAsAResultOfDeConsolidations	0	usd
CY2023	ambc	Decrease In Vie Long Term Debt As A Result Of De Consolidations DecreaseInVIELongTermDebtAsAResultOfDeConsolidations	133000000	usd
CY2022	ambc	Decrease In Vie Long Term Debt As A Result Of De Consolidations DecreaseInVIELongTermDebtAsAResultOfDeConsolidations	0	usd
CY2021	ambc	Decrease In Vie Long Term Debt As A Result Of De Consolidations DecreaseInVIELongTermDebtAsAResultOfDeConsolidations	0	usd
CY2023	ambc	Increase In Vie Long Term Debt As A Result Of Consolidations IncreaseInVIELongTermDebtAsAResultOfConsolidations	89000000	usd
CY2022	ambc	Increase In Vie Long Term Debt As A Result Of Consolidations IncreaseInVIELongTermDebtAsAResultOfConsolidations	0	usd
CY2021	ambc	Increase In Vie Long Term Debt As A Result Of Consolidations IncreaseInVIELongTermDebtAsAResultOfConsolidations	0	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	16000000	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
CY2023Q4	us-gaap	Restricted Cash RestrictedCash	12000000	usd
CY2022Q4	us-gaap	Restricted Cash RestrictedCash	14000000	usd
CY2021Q4	us-gaap	Restricted Cash RestrictedCash	5000000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	274000000	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
CY2023	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:10pt;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>
CY2023	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3
CY2023	us-gaap	Premiums Earned Net PremiumsEarnedNet	78000000	usd
CY2023	us-gaap	Insurance Commissions And Fees InsuranceCommissionsAndFees	51000000	usd
CY2023	us-gaap	Contractually Specified Servicing Fees Late Fees And Ancillary Fees Earned In Exchange For Servicing Financial Assets ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets	8000000	usd
CY2023	us-gaap	Net Investment Income NetInvestmentIncome	140000000	usd
CY2023	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-22000000	usd
CY2023	us-gaap	Revenues Revenues	269000000	usd
CY2023	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	-33000000	usd
CY2023	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	11000000	usd
CY2023	us-gaap	Insurance Commissions InsuranceCommissions	29000000	usd
CY2023	us-gaap	Operating Expenses OperatingExpenses	155000000	usd
CY2023	us-gaap	Depreciation Depreciation	2000000	usd
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	29000000	usd
CY2023	us-gaap	Interest Expense InterestExpense	64000000	usd
CY2023	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	257000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	12000000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7000000	usd
CY2023	us-gaap	Profit Loss ProfitLoss	5000000	usd
CY2023Q4	us-gaap	Assets Assets	8428000000	usd
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	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	Incurred Claims Financial Guarantee Insurance Contracts IncurredClaimsFinancialGuaranteeInsuranceContracts	-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
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2000000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	522000000	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
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18000000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	-16000000	usd
CY2021Q4	us-gaap	Assets Assets	12303000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	3000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	40000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	71000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1710000000	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 Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	106000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1395000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2197000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	3000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	40000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	71000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	2162000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	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 Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	106000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	1966000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	544000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	544000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	581000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	560000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	293000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	271000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	80000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	76000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	1500000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	1451000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2197000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	2162000000	usd
CY2023Q4	ambc	Debt Securities Available For Sale Continuous Unrealized Loss Position DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition	187000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	4000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	844000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	68000000	usd
CY2023Q4	ambc	Debt Securities Available For Sale Unrealized Loss Position Including Pledged Securities DebtSecuritiesAvailableForSaleUnrealizedLossPositionIncludingPledgedSecurities	1032000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	71000000	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	ambc	Debt Securities Accumulated Gross Unrealized Loss Before Tax Included Pledged Securities DebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxIncludedPledgedSecurities	106000000	usd
CY2023Q4	ambc	Average Percentage Of Unrealized Loss Versus Amortized Cost For Investment Grade Securities AveragePercentageOfUnrealizedLossVersusAmortizedCostForInvestmentGradeSecurities	0.07
CY2023Q4	ambc	Average Percentage Of Unrealized Loss Versus Amortized Cost For Below Investment Grade Securities AveragePercentageOfUnrealizedLossVersusAmortizedCostForBelowInvestmentGradeSecurities	0.05
CY2022	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	61000000	usd
CY2021	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	78000000	usd
CY2023	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	usd
CY2022	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	usd
CY2021	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	usd
CY2023	us-gaap	Interest Income Debt Securities Available For Sale Operating InterestIncomeDebtSecuritiesAvailableForSaleOperating	93000000	usd
CY2022	us-gaap	Interest Income Debt Securities Available For Sale Operating InterestIncomeDebtSecuritiesAvailableForSaleOperating	66000000	usd
CY2021	us-gaap	Interest Income Debt Securities Available For Sale Operating InterestIncomeDebtSecuritiesAvailableForSaleOperating	74000000	usd
CY2021	us-gaap	Net Investment Income NetInvestmentIncome	139000000	usd
CY2023	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-3000000	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
CY2023	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	-12000000	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
CY2023	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-22000000	usd
CY2022	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	31000000	usd
CY2021	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	7000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	3000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	3000000	usd
CY2023Q4	ambc	Fair Value Of Securities Deposited With Governmental Authorities FairValueOfSecuritiesDepositedWithGovernmentalAuthorities	24000000	usd
CY2022Q4	ambc	Fair Value Of Securities Deposited With Governmental Authorities FairValueOfSecuritiesDepositedWithGovernmentalAuthorities	23000000	usd
CY2023Q4	ambc	Fair Valueof Securities Depositedin Connectionwtih Letterof Credit FairValueofSecuritiesDepositedinConnectionwtihLetterofCredit	1000000	usd
CY2023Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	13000000	usd
CY2022Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	12000000	usd
CY2023	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	25000000	usd
CY2022	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	-48000000	usd
CY2021	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	23000000	usd
CY2023	us-gaap	Debt Securities Trading Realized Gain Loss DebtSecuritiesTradingRealizedGainLoss	18000000	usd
CY2022	us-gaap	Debt Securities Trading Realized Gain Loss DebtSecuritiesTradingRealizedGainLoss	-26000000	usd
CY2023Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	13000000	usd
CY2022Q4	ambc	Equity Securities Excluded From Fair Value EquitySecuritiesExcludedFromFairValue	12000000	usd
CY2023Q4	ambc	Fair Value Yield Rate FairValueYieldRate	0.112
CY2022Q4	ambc	Fair Value Yield Rate FairValueYieldRate	0.113
CY2023	ambc	Fair Value Financial Assets And Liabilities Transfers In Or Out Of Level3 FairValueFinancialAssetsAndLiabilitiesTransfersInOrOutOfLevel3	0
CY2023	us-gaap	Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings	0	usd
CY2022	us-gaap	Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings	0	usd
CY2021	us-gaap	Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings	0	usd
CY2023Q4	ambc	Financial Guarantee Gross Outstanding Principal FinancialGuaranteeGrossOutstandingPrincipal	26005000000	usd
CY2022Q4	ambc	Financial Guarantee Gross Outstanding Principal FinancialGuaranteeGrossOutstandingPrincipal	27551000000	usd
CY2023Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	19541000000	usd
CY2022Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	22613000000	usd
CY2023Q4	ambc	Financial Guarantee Outstanding Principal Ceded To Third Parties FinancialGuaranteeOutstandingPrincipalCededToThirdParties	6464000000	usd
CY2023Q4	ambc	Amount Of Insured Par Outstanding Ceded To Reinsurer AmountOfInsuredParOutstandingCededToReinsurer	2766000000	usd
CY2023	ambc	Ceded Principal Outstanding Major Reinsurer Percentage CededPrincipalOutstandingMajorReinsurerPercentage	0.106
CY2023Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	19541000000	usd
CY2022Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	22613000000	usd
CY2023Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	19541000000	usd
CY2022Q4	us-gaap	Participating Policies Amount In Force ParticipatingPoliciesAmountInForce	22613000000	usd
CY2023Q4	ambc	Financial Guarantee Gross Outstanding Principal And Interest FinancialGuaranteeGrossOutstandingPrincipalAndInterest	41733000000	usd
CY2022Q4	ambc	Financial Guarantee Gross Outstanding Principal And Interest FinancialGuaranteeGrossOutstandingPrincipalAndInterest	44734000000	usd
CY2023Q4	ambc	Net Financial Guarantee Principal And Interest In Force NetFinancialGuaranteePrincipalAndInterestInForce	29121000000	usd
CY2022Q4	ambc	Net Financial Guarantee Principal And Interest In Force NetFinancialGuaranteePrincipalAndInterestInForce	34975000000	usd
CY2023Q4	ambc	Total Net Par Outstanding Does Not Exceed This Percentage In Any Of The States In The Us TotalNetParOutstandingDoesNotExceedThisPercentageInAnyOfTheStatesInTheUS	0.06
CY2023	ambc	Percentage Of Highest Single Insured Risk Of Aggregate Net Par Amount Guaranteed PercentageOfHighestSingleInsuredRiskOfAggregateNetParAmountGuaranteed	0.046
CY2023	us-gaap	Direct Premiums Written DirectPremiumsWritten	249000000	usd
CY2023	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	40000000	usd
CY2023	us-gaap	Ceded Premiums Written CededPremiumsWritten	244000000	usd
CY2023	us-gaap	Premiums Written Net PremiumsWrittenNet	44000000	usd
CY2023	us-gaap	Direct Premiums Earned DirectPremiumsEarned	224000000	usd
CY2023	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	18000000	usd
CY2023	us-gaap	Ceded Premiums Earned CededPremiumsEarned	164000000	usd
CY2023	us-gaap	Premiums Earned Net PremiumsEarnedNet	78000000	usd
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
CY2023	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	0	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
CY2023	us-gaap	Premiums Earned Net Financial Guarantee Insurance Contracts PremiumsEarnedNetFinancialGuaranteeInsuranceContracts	78000000	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
CY2023Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	290000000	usd
CY2022Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	269000000	usd
CY2022Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	269000000	usd
CY2021Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	323000000	usd
CY2020Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	370000000	usd
CY2023	us-gaap	Premiums Written Gross PremiumsWrittenGross	210000000	usd
CY2022	us-gaap	Premiums Written Gross PremiumsWrittenGross	117000000	usd
CY2021	us-gaap	Premiums Written Gross PremiumsWrittenGross	10000000	usd
CY2023	us-gaap	Proceeds From Insurance Premiums Collected ProceedsFromInsurancePremiumsCollected	-208000000	usd
CY2022	us-gaap	Proceeds From Insurance Premiums Collected ProceedsFromInsurancePremiumsCollected	-139000000	usd
CY2021	us-gaap	Proceeds From Insurance Premiums Collected ProceedsFromInsurancePremiumsCollected	-43000000	usd
CY2023	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 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
CY2023	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable	8000000	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
CY2023	ambc	Financial Guarantee Insurance Contracts Consolidation Of Vie FinancialGuaranteeInsuranceContractsConsolidationOfVIE	-1000000	usd
CY2023	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Period Increase Decrease PremiumsReceivableAllowanceForDoubtfulAccountsPeriodIncreaseDecrease	1000000	usd
CY2022	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Period Increase Decrease PremiumsReceivableAllowanceForDoubtfulAccountsPeriodIncreaseDecrease	4000000	usd
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Period Increase Decrease PremiumsReceivableAllowanceForDoubtfulAccountsPeriodIncreaseDecrease	8000000	usd
CY2023	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments	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
CY2023Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	290000000	usd
CY2022Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	269000000	usd
CY2021Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	323000000	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
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	17000000	usd
CY2023	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-1000000	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
CY2023	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	0	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
CY2023	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	0	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
CY2023Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	4000000	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
CY2023Q4	ambc	Past Due Premiums PastDuePremiums	1000000	usd
CY2022Q4	ambc	Past Due Premiums PastDuePremiums	0	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During First Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFirstQuarterFollowingBalanceSheetDate	8000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During First Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFirstQuarterFollowingBalanceSheetDate	5000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Second Quarter Following The Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringSecondQuarterFollowingTheBalanceSheetDate	6000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Second Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringSecondQuarterFollowingBalanceSheetDate	4000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Third Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringThirdQuarterFollowingBalanceSheetDate	7000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Third Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringThirdQuarterFollowingBalanceSheetDate	4000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Fourth Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFourthQuarterFollowingBalanceSheetDate	5000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Fourth Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFourthQuarterFollowingBalanceSheetDate	4000000	usd
CY2023Q4	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
CY2023Q4	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	16000000	usd
CY2023Q4	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
CY2023Q4	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	16000000	usd
CY2023Q4	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
CY2023Q4	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	15000000	usd
CY2023Q4	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
CY2023Q4	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	14000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Five And Within10 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFiveAndWithin10YearsFromBalanceSheetDate	93000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Five And Within10 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFiveAndWithin10YearsFromBalanceSheetDate	55000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than10 And Within15 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan10AndWithin15YearsFromBalanceSheetDate	54000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than10 And Within15 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan10AndWithin15YearsFromBalanceSheetDate	28000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than15 And Within20 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan15AndWithin20YearsFromBalanceSheetDate	25000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than15 And Within20 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan15AndWithin20YearsFromBalanceSheetDate	9000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than20 And Within25 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan20AndWithin25YearsFromBalanceSheetDate	12000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than20 And Within25 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan20AndWithin25YearsFromBalanceSheetDate	4000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than25 And Within30 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan25AndWithin30YearsFromBalanceSheetDate	2000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than25 And Within30 Years From Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan25AndWithin30YearsFromBalanceSheetDate	1000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Premium Expected To Be Collected FinancialGuaranteeInsuranceContractsPremiumReceivablePremiumExpectedToBeCollected	310000000	usd
CY2023Q4	us-gaap	Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognized	173000000	usd
CY2023Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	893000000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	805000000	usd
CY2023Q4	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	137000000	usd
CY2022Q4	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	271000000	usd
CY2023Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	756000000	usd
CY2022Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	534000000	usd
CY2023	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="display:inline-block;vertical-align:top;width:46.428%"><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><td style="width:46.656%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:15.246%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:1.402%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:15.246%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:1.402%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:15.248%"></td><td style="width:0.1%"></td></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:7pt;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:7pt;font-weight:700;line-height:100%">2023</span></td><td colspan="3" style="padding:0 1pt"></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:7pt;font-weight:700;line-height:100%">2022</span></td><td colspan="3" style="padding:0 1pt"></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:7pt;font-weight:700;line-height:100%">2021</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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:7pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">534</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">$</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:7pt;font-weight:400;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><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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:7pt;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></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 5.5pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">Reinsurance recoverable</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:7pt;font-weight:700;line-height:100%">115</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">56 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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:7pt;font-weight:700;line-height:100%">419</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">Losses and loss expenses (benefit) incurred:</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 6.25pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">Current year</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">37</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">4 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></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:7pt;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:7pt;font-weight:700;line-height:100%">(69)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">(401)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></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:7pt;font-weight:400;line-height:100%">Total </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:4.55pt;font-weight:400;line-height:100%;position:relative;top:-2.44pt;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:7pt;font-weight:700;line-height:100%">(32)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 6.25pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">Current year</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">4</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">7 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></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:7pt;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:7pt;font-weight:700;line-height:100%">(194)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">(1,867)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 5.5pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">Total</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:7pt;font-weight:700;line-height:100%">(190)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;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><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">Foreign exchange effect</span></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">—</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">(2)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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:7pt;font-weight:700;line-height:100%">577</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">883 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"></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:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></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:7pt;font-weight:400;line-height:100%">Impact of VIE consolidation </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:4.55pt;font-weight:400;line-height:100%;position:relative;top:-2.44pt;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:7pt;font-weight:700;line-height:100%">(7)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">(464)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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></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:7pt;font-weight:400;line-height:100%">Reinsurance recoverable </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:4.55pt;font-weight:400;line-height:100%;position:relative;top:-2.44pt;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:7pt;font-weight:700;line-height:100%">186</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;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><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">115 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">56 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;border-bottom:1pt solid #000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;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:1pt solid #000;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:7pt;font-weight:700;line-height:100%">756</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;border-bottom:1pt solid #000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;border-bottom:1pt solid #000;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;border-bottom:1pt solid #000;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:7pt;font-weight:700;line-height:100%">534</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;border-bottom:1pt solid #000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;border-bottom:1pt solid #000;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;border-bottom:1pt solid #000;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:7pt;font-weight:700;line-height:100%">(522)</span></td><td style="background-color:#ffffff;border-bottom:1pt solid #000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></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 $(110), $(41) and $5 for the years ended December 31, 2023, 2022 and 2021, 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 Insurance segment. The losses and loss expense (benefit) incurred associated with changes in estimated R&W's for the year ended December 31, 2023, 2022 and 2021 was $0, $(123) and $20, respectively. Refer to </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-style:italic;font-weight:400;line-height:120%">Note 1. Background and Business </span></div></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-style:italic;font-weight:400;line-height:120%">Description</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%"> 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:9pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(3)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Ambac consolidated one, three and zero LFG VIEs during the years ended December 31, 2023, 2022 and 2021, respectively as further discussed in </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-style:italic;font-weight:400;line-height:120%">Note 11. Variable Interest Entities</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">. </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 $8, $0 and $0 as of December 31, 2023, 2022 and 2021, respectively, related to previously presented loss and loss adjustment expenses and subrogation.</span></div>
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CY2021Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	-522000000	usd
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CY2022Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	115000000	usd
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CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	-430000000	usd
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CY2023	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	-190000000	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
CY2023	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	0	usd
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CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	0	usd
CY2023Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	577000000	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
CY2023Q4	ambc	Impactof Vie Consolidationon Gross Lossand Loss Reserves ImpactofVIEConsolidationonGrossLossandLossReserves	-7000000	usd
CY2022Q4	ambc	Impactof Vie Consolidationon Gross Lossand Loss Reserves ImpactofVIEConsolidationonGrossLossandLossReserves	-464000000	usd
CY2023Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	186000000	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	56000000	usd
CY2023Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	756000000	usd
CY2022Q4	ambc	Liability For Claim And Claim Adjustment Expenses Net Of Subrogation Recoverables LiabilityForClaimAndClaimAdjustmentExpensesNetOfSubrogationRecoverables	534000000	usd
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CY2023	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	110000000	usd
CY2022	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	41000000	usd
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CY2023	ambc	Net Incurred Rmbs Subrogation Recoveries NetIncurredRMBSSubrogationRecoveries	0	usd
CY2022	ambc	Net Incurred Rmbs Subrogation Recoveries NetIncurredRMBSSubrogationRecoveries	123000000	usd
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CY2021Q4	ambc	Ceded Loss And Loss Expenses Paid Not Yet Recovered CededLossAndLossExpensesPaidNotYetRecovered	0	usd
CY2023Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Number Of Contracts Issued And Outstanding ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNumberOfContractsIssuedAndOutstanding	141	policies
CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Number Of Contracts Issued And Outstanding ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNumberOfContractsIssuedAndOutstanding	162	policies
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CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Interest ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingInterest	1750000000	usd
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CY2023Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Gross Undiscounted Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossUndiscountedClaimLiability	1202000000	usd
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CY2023Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedRmbsSubrogation	0	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedRmbsSubrogation	140000000	usd
CY2023Q4	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 Discount On Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnRmbsSubrogation	0	usd
CY2023Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation	0	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation	140000000	usd
CY2023Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedOtherSubrogation	263000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedOtherSubrogation	233000000	usd
CY2023Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnOtherSubrogation	69000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnOtherSubrogation	54000000	usd
CY2023Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityOtherSubrogation	194000000	usd
CY2022Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Other Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityOtherSubrogation	179000000	usd
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CY2022Q4	us-gaap	Schedule Of Insured Financial Obligations With Credit Deterioration Net Claim Liability ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNetClaimLiability	464000000	usd
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CY2023Q4	ambc	Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation	0	usd
CY2023Q4	ambc	Balance Of Rmbs Subrogation Recoveries Net Of Reinsurance BalanceOfRmbsSubrogationRecoveriesNetOfReinsurance	0	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
CY2023Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet	41000000	usd
CY2023Q4	ambc	Short Duration Insurance Contract Liability For Unpaid Clams And Allocated Claim Adjustment Expense Subtotal For Separately Presented ShortDurationInsuranceContractLiabilityForUnpaidClamsAndAllocatedClaimAdjustmentExpenseSubtotalForSeparatelyPresented	22000000	usd
CY2022Q4	ambc	Short Duration Insurance Contract Liability For Unpaid Clams And Allocated Claim Adjustment Expense Subtotal For Separately Presented ShortDurationInsuranceContractLiabilityForUnpaidClamsAndAllocatedClaimAdjustmentExpenseSubtotalForSeparatelyPresented	0	usd
CY2022Q4	ambc	Short Duration Insurance Contract Liability For Unpaid Clams And Allocated Claim Adjustment Expense Subtotal For Separately Presented ShortDurationInsuranceContractLiabilityForUnpaidClamsAndAllocatedClaimAdjustmentExpenseSubtotalForSeparatelyPresented	0	usd
CY2023Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	23000000	usd
CY2022Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	6000000	usd
CY2023Q4	ambc	Deferred Ceded Premiums And Reinsurance Recoverables DeferredCededPremiumsAndReinsuranceRecoverables	398000000	usd
CY2023Q4	us-gaap	Reinsurance Payable ReinsurancePayable	90000000	usd
CY2023Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	131000000	usd
CY2023Q4	ambc	Number Of Admitted Carriers Acquired In2022 NumberOfAdmittedCarriersAcquiredIn2022	3
CY2023Q4	ambc	Number Of Reinsurers Covering Majority NumberOfReinsurersCoveringMajority	3
CY2023Q4	ambc	Percentage Of Ceded Reinsurance Recoverable Represented By Top Three PercentageOfCededReinsuranceRecoverableRepresentedByTopThree	0.74
CY2023Q4	ambc	Reinsurance Recoverable Gross All Other ReinsuranceRecoverableGrossAllOther	50000000	usd
CY2023Q4	ambc	Unsecured Reinsurance Recoverable All Other UnsecuredReinsuranceRecoverableAllOther	21000000	usd
CY2023Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	195000000	usd
CY2023Q4	ambc	Unsecured Reinsurance Recoverables UnsecuredReinsuranceRecoverables	128000000	usd
CY2023Q4	ambc	Reinsurance Recoverable Credit Exposure ReinsuranceRecoverableCreditExposure	128000000	usd
CY2022Q4	ambc	Reinsurance Recoverable Credit Exposure ReinsuranceRecoverableCreditExposure	60000000	usd
CY2023Q4	ambc	Uncollateralized Credit Exposure Supoorted By Unlimited Uncapped Indemnity UncollateralizedCreditExposureSupoortedByUnlimitedUncappedIndemnity	44000000	usd
CY2022Q4	ambc	Uncollateralized Credit Exposure Supoorted By Unlimited Uncapped Indemnity UncollateralizedCreditExposureSupoortedByUnlimitedUncappedIndemnity	45000000	usd
CY2023Q4	ambc	Average Annual Rate Of Return AverageAnnualRateOfReturn	0.0586
CY2022Q4	ambc	Average Annual Rate Of Return AverageAnnualRateOfReturn	0.0322
CY2023	ambc	Prescribed Discount Rate Percentage PrescribedDiscountRatePercentage	0.0510
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	26000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	0	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	26000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	0	usd
CY2023Q4	ambc	Derivative Assets Net Amount DerivativeAssetsNetAmount	26000000	usd
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
CY2022Q4	us-gaap	Derivative Assets DerivativeAssets	27000000	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	0	usd
CY2022Q4	ambc	Derivative Assets Net Amount DerivativeAssetsNetAmount	27000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	35000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	0	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	35000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	35000000	usd
CY2023Q4	ambc	Derivative Liabilities Net Amount DerivativeLiabilitiesNetAmount	0	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	38000000	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	0	usd
CY2022Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	38000000	usd
CY2022Q4	ambc	Derivative Liabilities Gross Amount Of Collateral Cash And Securities Pledged Not Offset DerivativeLiabilitiesGrossAmountOfCollateralCashAndSecuritiesPledgedNotOffset	38000000	usd
CY2022Q4	ambc	Derivative Liabilities Net Amount DerivativeLiabilitiesNetAmount	0	usd
CY2023	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-1000000	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
CY2023	ambc	Derivative Gain Losson Derivatives Total Net DerivativeGainLossonDerivativesTotalNet	-64000000	usd
CY2022	ambc	Derivative Gain Losson Derivatives Total Net DerivativeGainLossonDerivativesTotalNet	694000000	usd
CY2021	ambc	Derivative Gain Losson Derivatives Total Net DerivativeGainLossonDerivativesTotalNet	-128000000	usd
CY2023Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	35000000	usd
CY2022Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	38000000	usd
CY2023Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	50000000	usd
CY2022Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	54000000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	61000000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	46000000	usd
CY2023	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	9000000	usd
CY2022	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	15000000	usd
CY2023Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	usd
CY2022Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	usd
CY2023Q4	us-gaap	Goodwill Goodwill	70000000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	61000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	292000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	312000000	usd
CY2023Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	307000000	usd
CY2022Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	326000000	usd
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	29000000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	47000000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	55000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	30000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	28000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	26000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	24000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	22000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	162000000	usd
CY2023	ambc	Variable Interest Entity Changein Fair Valueof Assetsand Liabilities VariableInterestEntityChangeinFairValueofAssetsandLiabilities	4000000	usd
CY2022	ambc	Variable Interest Entity Changein Fair Valueof Assetsand Liabilities VariableInterestEntityChangeinFairValueofAssetsandLiabilities	0	usd
CY2021	ambc	Variable Interest Entity Changein Fair Valueof Assetsand Liabilities VariableInterestEntityChangeinFairValueofAssetsandLiabilities	4000000	usd
CY2023	us-gaap	Variable Interest Entity Initial Consolidation Gain Or Loss VariableInterestEntityInitialConsolidationGainOrLoss	4000000	usd
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
CY2023	us-gaap	Variable Interest Entity Activity Between Vie And Entity Income Or Loss Before Tax VariableInterestEntityActivityBetweenVIEAndEntityIncomeOrLossBeforeTax	3000000	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
CY2023Q4	us-gaap	Variable Interest Entity Entity Maximum Loss Exposure Amount VariableInterestEntityEntityMaximumLossExposureAmount	20861000000	usd
CY2023Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Assets VariableInterestEntityNonconsolidatedCarryingAmountInsuranceAssets	351000000	usd
CY2023Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Insurance Liabilities VariableInterestEntityNonconsolidatedCarryingAmountInsuranceLiabilities	836000000	usd
CY2023Q4	ambc	Variable Interest Entity Nonconsolidated Carrying Amount Derivative Net Assets Or Liabilities VariableInterestEntityNonconsolidatedCarryingAmountDerivativeNetAssetsOrLiabilities	0	usd
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
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	519000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	0	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	41000000	usd
CY2023Q4	us-gaap	Debt Instrument Interest Rate Effective Percentage DebtInstrumentInterestRateEffectivePercentage	0.066
CY2023Q4	ambc	A5.1 Junior Surplus Notes General Account Due2020 Plus Accrued Interest A5.1JuniorSurplusNotesGeneralAccountDue2020PlusAccruedInterest	475000000	usd
CY2023	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	usd
CY2022	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	81000000	usd
CY2021	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	33000000	usd
CY2023	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	51000000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	31000000	usd
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	26000000	usd
CY2023	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	5000000	usd
CY2022	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	6000000	usd
CY2021	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	8000000	usd
CY2023Q4	us-gaap	Contract With Customer Receivable After Allowance For Credit Loss ContractWithCustomerReceivableAfterAllowanceForCreditLoss	10000000	usd
CY2022Q4	us-gaap	Contract With Customer Receivable After Allowance For Credit Loss ContractWithCustomerReceivableAfterAllowanceForCreditLoss	7000000	usd
CY2023Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	95000000	usd
CY2022Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	5000000	usd
CY2023Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	1000000	usd
CY2022Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	1000000	usd
CY2023	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	1000000	usd
CY2022	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	1000000	usd
CY2021	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	1000000	usd
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-253000000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	58000000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	74000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-296000000	usd
CY2023	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-19000000	usd
CY2022	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	15000000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	93000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-310000000	usd
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-160000000	usd
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-253000000	usd
CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	45195370	shares
CY2013Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2023	ambc	Warrant Exercised During Period Shares WarrantExercisedDuringPeriodShares	1503	shares
CY2022	ambc	Warrant Exercised During Period Shares WarrantExercisedDuringPeriodShares	0	shares
CY2021	ambc	Warrant Exercised During Period Shares WarrantExercisedDuringPeriodShares	132	shares
CY2023	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	29	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
CY2022Q1	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	20000000	usd
CY2022Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	15000000	usd
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	1930384	shares
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	325068	shares
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	19000000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	4000000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	522000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	-17000000	usd
CY2023	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	5000000	usd
CY2022	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	3000000	usd
CY2021	us-gaap	Minority Interest Change In Redemption Value MinorityInterestChangeInRedemptionValue	-12000000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	8000000	usd
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
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.18
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	11.48
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.61
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.18
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	11.31
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.61
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	45636649	shares
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
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46540706	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
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-29000000	usd
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
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	41000000	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
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	12000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	525000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	2000000	usd
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1000000	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
CY2023	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	8000000	usd
CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	7000000	usd
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	10000000	usd
CY2023	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	8000000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6000000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	12000000	usd
CY2023	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-2000000	usd
CY2023	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	1000000	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
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1000000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4000000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	6000000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7000000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18000000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7000000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18000000	usd
CY2023	ambc	Net Unrealized Losses On Securities Tax Effect NetUnrealizedLossesOnSecuritiesTaxEffect	12000000	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
CY2023	ambc	Change In Retirement Benefits Tax Effect ChangeInRetirementBenefitsTaxEffect	-1000000	usd
CY2022	ambc	Change In Retirement Benefits Tax Effect ChangeInRetirementBenefitsTaxEffect	0	usd
CY2021	ambc	Change In Retirement Benefits Tax Effect ChangeInRetirementBenefitsTaxEffect	0	usd
CY2023	ambc	Credit Risk Changes To Fair Value Options Tax Effect CreditRiskChangesToFairValueOptionsTaxEffect	0	usd
CY2022	ambc	Credit Risk Changes To Fair Value Options Tax Effect CreditRiskChangesToFairValueOptionsTaxEffect	0	usd
CY2021	ambc	Credit Risk Changes To Fair Value Options Tax Effect CreditRiskChangesToFairValueOptionsTaxEffect	0	usd
CY2023	ambc	Valuation Allowances And Reserves Charged To Equity ValuationAllowancesAndReservesChargedToEquity	9000000	usd
CY2022	ambc	Valuation Allowances And Reserves Charged To Equity ValuationAllowancesAndReservesChargedToEquity	-41000000	usd
CY2021	ambc	Valuation Allowances And Reserves Charged To Equity ValuationAllowancesAndReservesChargedToEquity	1000000	usd
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$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc

2024 Q1 Form 10-K Financial Statement

#000087450124000040 Filed on February 27, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMBC AMBAC FINANCIAL GROUP INC Stock $ambc

2024 Q1 Form 10-K Financial Statement

#000087450124000040 Filed on February 27, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc