XML 55 R44.htm IDEA: XBRL DOCUMENT
v3.23.2

Outstanding Exposure - Additional Information (Details) - USD ($) $ in Millions |  | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 26, 2023 | Jun. 30, 2023 | Jul. 28, 2023 | Jun. 23, 2023 | Dec. 31, 2022
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Loss Mitigation Securities |  | $ 1,300 |  |  | $ 1,300
Net par outstanding |  | 244,013 |  |  | 233,258
Guarantor, maximum exposure |  | 1,600 |  |  |
Subsequent Event |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  |  | $ 108 |  |
Puerto Rico Electric Power Authority |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Plaintiff debt capacity |  |  |  | $ 2,500 |
Plaintiff debt capacity allocated to settling creditors |  |  |  | 1,400 |
Plaintiff debt capacity allocated to bondholders and general unsecured creditors |  |  |  | $ 1,100 |
Claim received as restructuring bonds, percent |  |  |  | 12.50% |
Puerto Rico Electric Power Authority | Guarantee Obligations |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Damages sought, estimate | $ 2,400 |  |  |  |
Calculated collection period | 100 years |  |  |  |
Calculated discount rate | 7.00% |  |  |  |
Calculated discounted cash flows | $ 3,000 |  |  |  |
Additional calculated riscount rate | 20.00% |  |  |  |
Damages sought | $ 8,500 |  |  |  |
Puerto Rico |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | 1,349 |  |  | 1,361
Puerto Rico | Other Public Corporations |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | 125 |  |  |
Puerto Rico | PRHTA |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | 475 |  |  |
Public finance |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | 233,981 |  |  | 224,099
Structured finance |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | 10,032 |  |  | 9,159
Commitment to Provide Guarantees | Public finance |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Outstanding commitments to provide guaranties |  | 2,000 |  |  |
Commitment to Provide Guarantees | Structured finance |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Outstanding commitments to provide guaranties |  | $ 1,300 |  |  |
BIG |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Maximum period of liquidity claims (in years) |  | 1 year |  |  |
Net par outstanding |  | $ 5,634 |  |  | 5,892
Residual value insurance policies exposure downgraded |  | 144 |  |  | 144
Net Exposure |  | 84 |  |  | 84
BIG | Puerto Rico |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | 1,300 |  |  | 1,400
BIG | Public finance |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | 4,566 |  |  | 4,777
BIG | Structured finance |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Net par outstanding |  | $ 1,068 |  |  | $ 1,115
Minimum |  |  |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |  |  |
Probability of paying more claims than being reimbursed (as a percent) |  | 50.00% |  |  |

X
- Definition Claim Received as Restructuring Bonds, Percent + References No definition available. + Details
Name: | ago_ClaimReceivedAsRestructuringBondsPercent
Namespace Prefix: | ago_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents the outstanding principal amounts of the securities insured and purchased by the Company, and for which it has expected losses to be paid, in order to mitigate the economic effect of insured losses ("loss mitigation securities"). + References No definition available. + Details
Name: | ago_InsuredFinancialObligationsLossMitigationSecurities
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Represents the period within which the entity expects the reimbursement of the liquidity claims. + References No definition available. + Details
Name: | ago_InsuredFinancialObligationsMaximumPeriodofLiquidityClaims
Namespace Prefix: | ago_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the outstanding principal amounts of the underlying insured obligations for financial guaranty contracts, after netting out ceded contracts. + References No definition available. + Details
Name: | ago_InsuredFinancialObligationsOutstandingPrincipalAmountNet
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Probability that, on a present value basis, the entity will pay more claims over the life of that transaction than it will ultimately have been reimbursed. + References No definition available. + Details
Name: | ago_InsuredFinancialObligationsProbabilityofPayingMoreClaimsthanReimbursedPercentage
Namespace Prefix: | ago_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Loss Contingency, Damages Sought, Additional Calculated Discount Rate + References No definition available. + Details
Name: | ago_LossContingencyDamagesSoughtAdditionalCalculatedDiscountRate
Namespace Prefix: | ago_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loss Contingency, Damages Sought, Calculated Collection Period + References No definition available. + Details
Name: | ago_LossContingencyDamagesSoughtCalculatedCollectionPeriod
Namespace Prefix: | ago_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loss Contingency, Damages Sought, Calculated Discount Rate + References No definition available. + Details
Name: | ago_LossContingencyDamagesSoughtCalculatedDiscountRate
Namespace Prefix: | ago_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loss Contingency, Damages Sought, Calculated Discounted Cash Flows + References No definition available. + Details
Name: | ago_LossContingencyDamagesSoughtCalculatedDiscountedCashFlows
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Loss Contingency, Damages Sought, Estimate + References No definition available. + Details
Name: | ago_LossContingencyDamagesSoughtEstimate
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Plaintiff Debt Capacity + References No definition available. + Details
Name: | ago_PlaintiffDebtCapacity
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Plaintiff Debt Capacity, Bondholders and General Unsecured Creditors + References No definition available. + Details
Name: | ago_PlaintiffDebtCapacityBondholdersAndGeneralUnsecuredCreditors
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Plaintiff Debt Capacity, Settling Creditors + References No definition available. + Details
Name: | ago_PlaintiffDebtCapacitySettlingCreditors
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition [Line Items] for Schedule of Insured Financial Obligations [Table] + References No definition available. + Details
Name: | ago_ScheduleofInsuredFinancialObligationsLineItems
Namespace Prefix: | ago_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Specialty Business, Gross Par + References No definition available. + Details
Name: | ago_SpecialtyBusinessGrossPar
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Specialty Business, Net Par + References No definition available. + Details
Name: | ago_SpecialtyBusinessNetPar
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482425/460-10-50-4 + Details
Name: | us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The value (monetary amount) of the award the plaintiff seeks in the legal matter. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-4 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-9 + Details
Name: | us-gaap_LossContingencyDamagesSoughtValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
Name: | us-gaap_OtherCommitment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=ago_PuertoRicoElectricPowerAuthorityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_GuaranteeObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | ago_LoansInsuredOrGuaranteeForGovernmentAuthoritiesAxis=ago_PublicCorporationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ago_LoansInsuredOrGuaranteeForGovernmentAuthoritiesAxis=ago_PuertoRicoHighwaysAndTransportationAuthorityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnderlyingAssetClassAxis=ago_PublicFinanceMember
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: |

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=ago_CommitmenttoProvideGuaranteesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InternalCreditAssessmentAxis=us-gaap_InternalNoninvestmentGradeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |