XML 80 R69.htm IDEA: XBRL DOCUMENT
v3.23.2

Contracts Accounted for as Credit Derivatives - Credit Derivatives Subordination and Ratings (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2023 | Dec. 31, 2022
Credit Derivatives |  |
Estimated remaining weighted average life of credit derivatives (in years) | 12 years 7 months 6 days | 12 years 9 months 18 days
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | $ 3,205 | $ 3,203
Net Fair Value Asset (Liability) | (57) | (162)
Expected loss to be recovered | 3 | 3
Public finance | United States |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 1,131 | 1,175
Net Fair Value Asset (Liability) | (17) | (79)
Public finance | Non United States |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 1,611 | 1,565
Net Fair Value Asset (Liability) | (22) | (58)
Structured finance | United States |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 336 | 342
Net Fair Value Asset (Liability) | (16) | (22)
Structured finance | Non United States |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 127 | 121
Net Fair Value Asset (Liability) | $ (2) | $ (3)

X
- Definition Expected Loss on Credit Derivative to Be Paid (Recovered), Including Representation and Warranty Liability (Benefit) + References No definition available. + Details
Name: | ago_ExpectedLossOnCreditDerivativeToBePaidRecoveredIncludingRepresentationAndWarrantyLiabilityBenefit
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | ago_FinancialGuarantyContractsAccountedForAsCreditDerivativesAbstract
Namespace Prefix: | ago_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the outstanding principal amounts of the underlying insured obligations that are accounted for as credit derivatives, net of protection purchased. + References No definition available. + Details
Name: | ago_FinancialGuarantyContractsAccountedforasCreditDerivativesOutstandingPrincipalAmount
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Average period covered by credit risk derivative contracts, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4K -Subparagraph (a)(1) -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4K + Details
Name: | us-gaap_AverageTermOfCreditRiskDerivatives1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_CreditDerivativesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value of credit risk derivative asset after deduction of credit risk derivative liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4K -Subparagraph (c) -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4K + Details
Name: | us-gaap_CreditRiskDerivativesAtFairValueNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_UnderlyingAssetClassAxis=ago_PublicFinanceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=ago_NonUnitedStatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnderlyingAssetClassAxis=us-gaap_StructuredFinanceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |