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v2.4.1.9

Fair Value Measurements - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 1 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 30, 2013 | Sep. 30, 2014 | Dec. 31, 2014 | Dec. 31, 2013
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Coupon rate | 5.01%ambc_FairValueInputsCouponRate |  |  |
Credit valuation adjustment included in fair value of credit derivative liabilities |  |  | $ 15,910 us-gaap_DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities | $ 38,966 us-gaap_DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities
Credit valuation adjustment included in fair value of derivative liabilities other than credit derivatives |  |  | 64,547 ambc_DerivativesCreditRiskValuationAdjustmentDerivativeLiabilitiesOtherThanCreditDerivatives | 48,425 ambc_DerivativesCreditRiskValuationAdjustmentDerivativeLiabilitiesOtherThanCreditDerivatives
Percentage of CDS gross par outstanding used in the determination of CDS fair values |  |  | 85.00%ambc_PercentageOfCreditDerivativesGrossParOutstandingUsingThirdPartyReferenceObligationQuotesInDeterminationOfFairValue |
Percentage of CDS derivative liability used in the determination of CDS fair values |  |  | 66.00%ambc_PercentageOfCreditDerivativesLiabilityUsingThirdPartyReferenceObligationQuotesInDeterminationOfFairValue |
Percentage of CDS gross par outstanding using internally estimated reference obligation prices in determination of fair value |  |  | 15.00%ambc_PercentageOfCreditDerivativeGrossParOutstandingUsingInternallyEstimatedReferenceObligationPricesInDeterminationOfFairValue |
Percentage of CDS liability using internally estimated reference obligation prices in determination of fair value |  |  | 34.00%ambc_PercentageOfCreditDerivativeLiabilityUsingInternallyEstimatedReferenceObligationPricesInDeterminationOfFairValue |
Additional basis point fee need to receive for issuing a CDS on obligation |  | 0.05%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesHypotheticalIncrementalFee |  |
Additional basis points fee increase on change of reference obligation spread |  | 0.15%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesHypotheticalIncrementalFeeWithCreditDeterioration |  |
Revised relative change ratio of CDS fee to cash market spread |  |  | 73.20%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesRevisedRelativeChangeRatio |
Estimated remaining life |  |  | 8 years |
Notional outstanding |  |  | 1,529,759 invest_DerivativeNotionalAmount | 2,776,103 invest_DerivativeNotionalAmount
Derivative liabilities |  |  | 73,459 us-gaap_DerivativeFairValueOfDerivativeLiability | 94,322 us-gaap_DerivativeFairValueOfDerivativeLiability
Percentage of profit margin |  |  | 17.00%us-gaap_FairValueInputsLongTermNetOfTaxOperatingIncomeMarginPercent | 17.00%us-gaap_FairValueInputsLongTermNetOfTaxOperatingIncomeMarginPercent
Weighted average discounted rate of estimated future premium payments to be paid by the VIEs |  |  | 2.70%ambc_EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate | 3.00%ambc_EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate
Credit Derivatives [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
CVA percentage |  |  | 17.80%ambc_PercentageOfCreditValueAdjustment / us-gaap_CreditDerivativesByContractTypeAxis = ambc_CreditDerivativesMember | 29.20%ambc_PercentageOfCreditValueAdjustment / us-gaap_CreditDerivativesByContractTypeAxis = ambc_CreditDerivativesMember
European ABS Transactions [Member] | Level 3 [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Fair value of consolidated VIE debt obligations valued using unobservable inputs by asset class |  |  | 1,070,439 ambc_FairValueOfConsolidatedVariableInterestEntityDebtObligationsValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = ambc_EuropeanTransactionsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 1,329,985 ambc_FairValueOfConsolidatedVariableInterestEntityDebtObligationsValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = ambc_EuropeanTransactionsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
US Commercial ABS Transaction [Member] | Level 3 [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Fair value of consolidated VIE debt obligations valued using unobservable inputs by asset class |  |  | 193,225 ambc_FairValueOfConsolidatedVariableInterestEntityDebtObligationsValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = ambc_UnitedStatesTransactionsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 184,620 ambc_FairValueOfConsolidatedVariableInterestEntityDebtObligationsValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = ambc_UnitedStatesTransactionsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Minimum [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Basis point fee received for issuing a CDS on reference obligation base fee |  | 0.20%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesBaseFee / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
Credit spread of reference obligation of a base transaction |  |  | 0.80%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesBaseReferenceObligationSpread / us-gaap_RangeAxis = us-gaap_MinimumMember |
Relative change ratio of CDS fee to cash market spread |  |  | 25.00%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesBaseRelativeChangeRatio / us-gaap_RangeAxis = us-gaap_MinimumMember |
Maximum [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Basis point fee received for issuing a CDS on reference obligation hypothetical fee |  | 0.25%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesRevisedHypotheticalFee / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
Relative change ratio of CDS fee to cash market spread |  |  | 35.00%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesRevisedHypotheticalFeeWithCreditDownGrade / us-gaap_RangeAxis = us-gaap_MaximumMember |
Credit spread of reference obligation of revised transaction |  | 1.00%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesRevisedHypotheticalReferenceObligationSpreadTwo / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
Internal Credit Rating [Member] | Minimum [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Revised relative change ratio of CDS fee to cash market spread |  |  | 33.00%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesRevisedRelativeChangeRatio / invest_CreditRatingSourceAxis = us-gaap_InternalCreditAssessmentDomain / us-gaap_RangeAxis = us-gaap_MinimumMember |
Internal Credit Rating [Member] | Maximum [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Full relative change ratio of CDS fee to cash market spread |  |  | 100.00%ambc_FairValueMeasurementProcessDescriptionForCreditDerivativesFullRelativeChangeRatio / invest_CreditRatingSourceAxis = us-gaap_InternalCreditAssessmentDomain / us-gaap_RangeAxis = us-gaap_MaximumMember |
Successor [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Notional outstanding |  |  | 1,529,759 invest_DerivativeNotionalAmount / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 2,776,103 invest_DerivativeNotionalAmount / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Available-for-sale Securities |  |  | 5,150,018 us-gaap_AvailableForSaleSecurities / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 6,282,658 us-gaap_AvailableForSaleSecurities / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Fixed Income Securities [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Percentage of investment portfolio valued using dealer quotes |  |  | 10.00%ambc_PercentageOfInvestmentPortfolioValuedUsingDealerQuotes / us-gaap_FairValueByAssetClassAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 11.00%ambc_PercentageOfInvestmentPortfolioValuedUsingDealerQuotes / us-gaap_FairValueByAssetClassAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | U.S. Agency Obligations [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Coupon rate |  |  |  | 6.98%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Fair Value Inputs Maturity |  |  |  | 1 year 4 months 13 days
Fair Value Inputs Yield |  |  |  | 0.39%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | U.S. Agency Obligations [Member] | Level 3 [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Fair value of investments in corporate obligation securities classified as Level 3 in the fair value hierarchy |  |  | 0 ambc_FairValueOfInvestmentsInSecuritiesValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 208 ambc_FairValueOfInvestmentsInSecuritiesValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Available-for-sale Securities |  |  | 0 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 208 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Asset-backed Securities [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Coupon rate |  |  |  | 0.64%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Fair Value Inputs Maturity |  |  |  | 7 years 1 month 24 days
Fair Value Inputs Yield |  |  |  | 5.17%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Asset-backed Securities [Member] | Level 3 [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Fair value of investments in corporate obligation securities classified as Level 3 in the fair value hierarchy |  |  | 0 ambc_FairValueOfInvestmentsInSecuritiesValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 64,073 ambc_FairValueOfInvestmentsInSecuritiesValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Available-for-sale Securities |  |  | 0 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 64,073 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Residential Mortgage-Backed Securities [Member] | Level 3 [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Available-for-sale Securities |  |  | 194,393 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 0 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Corporate Obligations [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Coupon rate |  |  | 0.345%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 0.345%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Fair Value Inputs Maturity |  |  | 19 years 1 month 21 days | 20 years 1 month 19 days
Fair Value Inputs Yield |  |  | 4.93%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 6.30%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Corporate Obligations [Member] | Level 3 [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Fair value of investments in corporate obligation securities classified as Level 3 in the fair value hierarchy |  |  | 3,808 ambc_FairValueOfInvestmentsInSecuritiesValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 3,502 ambc_FairValueOfInvestmentsInSecuritiesValuedUsingUnobservableInputsByAssetClass / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Available-for-sale Securities |  |  | 3,808 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 3,502 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Collateralized Debt Obligations [Member] | Level 3 [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Available-for-sale Securities |  |  | $ 0 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_CollateralizedDebtObligationsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | $ 0 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByAssetClassAxis = us-gaap_CollateralizedDebtObligationsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | European ABS Transactions [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Coupon rate |  |  | 0.30%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = ambc_EuropeanTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 0.72%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = ambc_EuropeanTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Fair Value Inputs Maturity |  |  | 21 years 2 months 30 days | 17 years 9 months 40 days
Fair Value Inputs Yield |  |  | 9.52%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = ambc_EuropeanTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 8.02%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = ambc_EuropeanTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | US Commercial ABS Transaction [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Coupon rate |  |  | 5.88%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = ambc_UnitedStatesTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 6.11%ambc_FairValueInputsCouponRate / us-gaap_FairValueByAssetClassAxis = ambc_UnitedStatesTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Fair Value Inputs Maturity |  |  | 15 years 10 months 4 days | 6 years 9 months 28 days
Fair Value Inputs Yield |  | 7.37%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = ambc_UnitedStatesTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  | 11.95%ambc_FairValueInputsYield / us-gaap_FairValueByAssetClassAxis = ambc_UnitedStatesTransactionsMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Minimum [Member] | Fixed Income Securities [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Percentage of investment portfolio valued using internal valuation models |  |  | 4.00%ambc_PercentageOfInvestmentPortfolioValuedUsingInternalValuationModels / us-gaap_FairValueByAssetClassAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 1.00%ambc_PercentageOfInvestmentPortfolioValuedUsingInternalValuationModels / us-gaap_FairValueByAssetClassAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Successor [Member] | Maximum [Member] | Fixed Income Securities [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Percentage of investment portfolio valued using external pricing services |  |  | 86.00%ambc_PercentageOfInvestmentPortfolioValuedUsingExternalPricingServices / us-gaap_FairValueByAssetClassAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 88.00%ambc_PercentageOfInvestmentPortfolioValuedUsingExternalPricingServices / us-gaap_FairValueByAssetClassAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember
Variable Interest Entities [Member] |  |  |  |
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] |  |  |  |
Weighted average discounted rate of estimated future premium payments to be paid by the VIEs |  |  | 4.10%ambc_EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate / dei_LegalEntityAxis = ambc_VariableInterestEntityMember | 5.10%ambc_EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate / dei_LegalEntityAxis = ambc_VariableInterestEntityMember

X
- Definition Amount of credit risk valuation adjustment to derivative liabilities other than credit derivatives, to properly reflect the credit quality of the entity. + References No definition available. + Details
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- Definition Hypothetical base fee received on a credit derivative contract used in the description of the valuation processes in place for fair value measurement of credit derivatives. + References No definition available. + Details
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- Definition Hypothetical base relative change ratio for a credit derivative contract used in the description of the valuation processes in place for fair value measurement of credit derivatives. + References No definition available. + Details
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- Definition Hypothetical incremental credit derivative fee given a certain credit downgrade used in the description of the valuation processes in place for fair value measurement of credit derivative. + References No definition available. + Details
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- Definition Hypothetical remaining contract life used in the description of the valuation processes in place for fair value measurement of credit derivatives. + References No definition available. + Details
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- Definition Hypothetical revised fee required on credit derivative given a certain credit downgrade used in the description of the valuation processes in place for fair value measurement of credit derivatives. + References No definition available. + Details
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