XML 109 R89.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Financial Guarantee Insurance - Summary of Percentage Ceded to Reinsurers and Reinsurance Recoverable and Rating Levels (Detail) $ in Millions | Dec. 31, 2021 USD ($)
--- | ---
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |
Net unsecured reinsurance recoverable | $ 31
Reinsurance Recoverables, Gross | $ 55
Percentage of Ceded Reinsurance Recoverable Represented by Top Three | 98.00%
QBE Insurance Corporation | Property and Casualty, Commercial Insurance |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |
Net unsecured reinsurance recoverable | $ 27
Reinsurance Recoverables, Gross | 27
Assured Guaranty Re Ltd [Member] | Financial Guarantee |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |
Net unsecured reinsurance recoverable | 0
Reinsurance Recoverables, Gross | 18
Sompo Japan Nipponkoa Holdings, Inc [Member] | Financial Guarantee |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |
Net unsecured reinsurance recoverable | 0
Reinsurance Recoverables, Gross | $ 9

X
- Definition Percentage of Ceded Reinsurance Recoverable Represented by Top Three + References No definition available. + Details
Name: | ambc_PercentageOfCededReinsuranceRecoverableRepresentedByTopThree
Namespace Prefix: | ambc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] + References No definition available. + Details
Name: | ambc_SummaryOfCededParAndNetUnsecuredReinsuranceRecoverableLineItems
Namespace Prefix: | ambc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents reinsurance recoverables on paid and unpaid losses and deferred ceded premiums, net of ceded premiums payables due to reinsurers, letters of credit, and collateral posted for the benefit of the cedant. + References No definition available. + Details
Name: | ambc_UnsecuredReinsuranceRecoverables
Namespace Prefix: | ambc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524 + Details
Name: | us-gaap_ReinsuranceRecoverablesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_CededCreditRiskAxis=ambc_QBEInsuranceCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ScheduleOfMalpracticeInsuranceTypeAndTierIdentifierAxis=us-gaap_PropertyAndCasualtyCommercialInsuranceProductLineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=ambc_AssuredGuarantyReLtdMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ScheduleOfMalpracticeInsuranceTypeAndTierIdentifierAxis=us-gaap_FinancialGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=ambc_SompoJapanNipponkoaInsuranceIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |