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v2.4.1.9

Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended | 4 Months Ended | 3 Months Ended | 8 Months Ended |
--- | --- | --- | --- | --- | ---
Dec. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2012 | Apr. 30, 2013 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Jun. 30, 2012
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument Principal Amount Subject To Repurchase |  |  | $ 939,179 ambc_DebtInstrumentPrincipalAmountSubjectToRepurchase |  |  |  |  |  |  |
Surplus Note Repurchase Amount Not Approved | 150,000 ambc_SurplusNoteRepurchaseAmountNotApproved |  |  |  |  |  |  |  |  |
5.1% Surplus Notes, General Account, Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 10.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member |  |  | 10.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  |  | 789,179 us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member |  |  |  |  |  |  |
Net realized losses on extinguishment of debt |  | 71,590 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member | 177,745 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member |  |  |  |  |  |  |
Debt Instrument, Face Amount | 1,210,821 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member | 893,300 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member |  |  | 893,300 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member |  |  |  | 1,210,821 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member |
5.1% Surplus Notes, Segregated Account, Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 10.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member |  |  | 10.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member |  |  |  |  |
Aggregate Payment To Repurchase Surplus Notes |  |  |  |  |  |  |  |  |  | 188,446 ambc_AggregatePaymentToRepurchaseSurplusNotes / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member
Net realized losses on extinguishment of debt |  | 3,134 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member |  |  |  |  |  |  |  |
Debt Instrument, Face Amount | 53,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member | 39,102 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member |  |  | 39,102 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member |  |  |  | 53,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member |
5.1% Junior Surplus Notes, Segregated Account Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 19.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  | 19.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  |  |  |
Debt Instrument, Face Amount | 28,039 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member | 378,039 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  | 378,039 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  | 28,039 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |
One State Street [Member] | 5.1% Junior Surplus Notes, Segregated Account Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  | 28,039 us-gaap_DebtInstrumentFaceAmount / us-gaap_CounterpartyNameAxis = ambc_OneStateStreetMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  | 28,039 us-gaap_DebtInstrumentFaceAmount / us-gaap_CounterpartyNameAxis = ambc_OneStateStreetMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  |  |  |
Variable Interest Entity, Not Primary Beneficiary, Aggregated Disclosure [Member] | 5.1% Junior Surplus Notes, Segregated Account Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 8.40%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_CounterpartyNameAxis = ambc_Ambc_NonconsolidatedVIETrustMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  | 8.40%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_CounterpartyNameAxis = ambc_Ambc_NonconsolidatedVIETrustMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member |  |  |  |  |
Predecessor [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  | 155,271 us-gaap_LongTermDebt / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember |  |  |  |  |  |
Net realized losses on extinguishment of debt |  |  | (177,580)us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember | 0 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember |  |  |  |  |  |
Predecessor [Member] | 5.1% Surplus Notes, General Account, Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 53.90%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember |  |  |  |  |  |
Predecessor [Member] | 5.1% Surplus Notes, Segregated Account, Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 52.80%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember |  |  |  |  |  |
Predecessor [Member] | 5.1% Junior Surplus Notes, Segregated Account Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 58.30%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember |  |  |  |  |  |
Successor [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt | 963,178 us-gaap_LongTermDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 971,116 us-gaap_LongTermDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  | 940,313 us-gaap_LongTermDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 971,116 us-gaap_LongTermDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  | 963,178 us-gaap_LongTermDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Net realized losses on extinguishment of debt |  | (74,724)us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | (74,724)us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 0 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 0 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 0 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 0 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Successor [Member] | Ambac Assurance Corporation [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt | 963,178 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 971,116 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 971,116 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  | 963,178 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Successor [Member] | Ambac Assurance Corporation [Member] | 5.1% Surplus Notes, General Account, Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt | 909,186 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 696,330 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 696,330 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  | 909,186 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Successor [Member] | Ambac Assurance Corporation [Member] | 5.1% Surplus Notes, Segregated Account, Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt | 39,797 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 30,479 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 30,479 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  | 39,797 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Successor [Member] | Ambac Assurance Corporation [Member] | 5.1% Junior Surplus Notes, Segregated Account Due 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt | 14,195 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 244,307 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 244,307 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  | 14,195 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_LongtermDebtTypeAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Successor [Member] | Variable Interest Entities [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.65%us-gaap_DebtInstrumentInterestRateStatedPercentage / dei_LegalEntityAxis = ambc_VariableInterestEntityMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  |  |  |  |  | 6.65%us-gaap_DebtInstrumentInterestRateStatedPercentage / dei_LegalEntityAxis = ambc_VariableInterestEntityMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Long-term debt | 14,091,753 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_VariableInterestEntityMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember | 12,882,076 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_VariableInterestEntityMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 12,882,076 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_VariableInterestEntityMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  | 14,091,753 us-gaap_LongTermDebt / dei_LegalEntityAxis = ambc_VariableInterestEntityMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Successor [Member] | 5.1% Surplus Notes, General Account, Due 2020 [Member] | Ambac Assurance Corporation [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  |  | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1SurplusNotesGeneralAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Debt Instruments Maturity Year | 2020 | 2020 |  |  |  |  |  |  |  |
Successor [Member] | 5.1% Surplus Notes, Segregated Account, Due 2020 [Member] | Ambac Assurance Corporation [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  |  | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1SurplusNotesSegregatedAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Debt Instruments Maturity Year | 2020 | 2020 |  |  |  |  |  |  |  |
Successor [Member] | 5.1% Junior Surplus Notes, Segregated Account Due 2020 [Member] | Ambac Assurance Corporation [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  |  |  | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |  |  | 5.10%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = ambc_A5.1JuniorSurplusNotesSegregatedAccountDue2020Member / dei_LegalEntityAxis = ambc_AmbacAssuranceCorporationMember / us-gaap_StatementScenarioAxis = us-gaap_SuccessorMember |
Debt Instruments Maturity Year | 2020 | 2020 |  |  |  |  |  |  |  |
Consolidated Variable Interest Entities [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Unpaid Principal Amount Of Fixed Rate Debt Accounted For Under Fair Value Option | 14,251,771 ambc_UnpaidPrincipalAmountOfFixedRateDebtAccountedForUnderFairValueOption / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember | 11,925,499 ambc_UnpaidPrincipalAmountOfFixedRateDebtAccountedForUnderFairValueOption / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  | 11,925,499 ambc_UnpaidPrincipalAmountOfFixedRateDebtAccountedForUnderFairValueOption / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  |  | 14,251,771 ambc_UnpaidPrincipalAmountOfFixedRateDebtAccountedForUnderFairValueOption / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months |  | 77,920 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  | 77,920 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Two |  | 0 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  | 0 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Three |  | 0 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  | 0 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Four |  | 162,939 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  | 162,939 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  |  |  |
Long-term Debt, Maturities, Repayments of Principal in Year Five |  | $ 393,235 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  | $ 393,235 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  |  |  |
Consolidated Variable Interest Entities [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 0.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember | 0.69%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  | 0.69%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |  |  |  | 0.50%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis = ambc_ConsolidatedVariableInterestEntitiesMember |
Consolidated Variable Interest Entities [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
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- Definition Aggregate payment to repurchase surplus notes. + References No definition available. + Details
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- Definition Aggregate principal amount of surplus notes that may be repurchased at a discount under call option agreements. + References No definition available. + Details
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- Definition Principal amount of surplus notes for which repurchase approval was declined by the insurance regulator. + References No definition available. + Details
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- Definition Unpaid Principal Amount Of Fixed Rate Debt Accounted For Under Fair Value Option + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Face (par) amount of the original debt instrument that was repurchased. + References No definition available. + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629 + Details
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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
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