XML 59 R46.htm IDEA: XBRL DOCUMENT
v3.25.3

Expected Loss to be Paid (Recovered) - Net Expected Loss to be Paid After Net Expected Recoveries for Breaches of R&W Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Net expected loss to be paid (recovered), beginning of period | $ 186 | $ 447 | $ 106 | $ 505 | $ 505
Accretion of discount | 2 | 5 | 5 | 14 |
Changes in discount rates | 0 | 3 | 6 | 1 |
Changes in timing and assumptions | (40) | (42) | (28) | (35) |
Total economic loss development (benefit) | (38) | (34) | (17) | (20) |
Net (paid) recovered losses | (44) | (107) | 15 | (179) |
Net expected loss to be paid (recovered), end of period | 104 | 306 | 104 | $ 306 | 106
Period after the end of the reporting period within which the ceded paid losses are typically settled (in days) |  |  |  | 45 days |
Public finance |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Net expected loss to be paid (recovered), beginning of period | 192 | 411 | 116 | $ 418 | 418
Total economic loss development (benefit) | (8) | 23 | 87 | 49 |
Net (paid) recovered losses | (81) | (115) | (100) | (148) |
Net expected loss to be paid (recovered), end of period | 103 | 319 | 103 | 319 | 116
Other structured finance |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Net expected loss to be paid (recovered), beginning of period | 29 | 36 | 33 | 44 | 44
Total economic loss development (benefit) | 1 | (1) | (64) | 0 |
Net (paid) recovered losses | 30 | (2) | 91 | (11) |
Net expected loss to be paid (recovered), end of period | 60 | 33 | 60 | 33 | 33
Structured finance |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Net expected loss to be paid (recovered), beginning of period | (6) | 36 | (10) | 87 | 87
Total economic loss development (benefit) | (30) | (57) | (104) | (69) |
Net (paid) recovered losses | 37 | 8 | 115 | (31) |
Net expected loss to be paid (recovered), end of period | 1 | (13) | $ 1 | (13) | $ (10)
Minimum |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Risk free discount rate |  |  | 1.92% |  | 1.98%
Maximum |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Risk free discount rate |  |  | 5.70% |  | 5.22%
Weighted Average |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Risk free discount rate |  |  | 4.02% |  | 4.38%
United States | Public finance |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Net expected loss to be paid (recovered), beginning of period | 53 | 374 | $ 18 | 398 | $ 398
Total economic loss development (benefit) | (2) | (23) | 51 | (14) |
Net (paid) recovered losses | (81) | (113) | (99) | (146) |
Net expected loss to be paid (recovered), end of period | (30) | 238 | (30) | 238 | 18
United States | RMBS |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Net expected loss to be paid (recovered), beginning of period | (35) | 0 | (43) | 43 | 43
Total economic loss development (benefit) | (31) | (56) | (40) | (69) |
Net (paid) recovered losses | 7 | 10 | 24 | (20) |
Net expected loss to be paid (recovered), end of period | (59) | (46) | (59) | (46) | (43)
Non-U.S. public finance | Public finance |  |  |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |  |  |
Net expected loss to be paid (recovered), beginning of period | 139 | 37 | 98 | 20 | 20
Total economic loss development (benefit) | (6) | 46 | 36 | 63 |
Net (paid) recovered losses | 0 | (2) | (1) | (2) |
Net expected loss to be paid (recovered), end of period | $ 133 | $ 81 | $ 133 | $ 81 | $ 98

X
- Definition Guarantor Obligations, Liability For Unpaid Claims And Claims Adjustment Expense, Claims Paid After Recoveries for Representations and Warranties + References No definition available. + Details
Name: | ago_GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Guarantor Obligations, Net Expected Loss Development After Recoveries for Representations and Warranties + References No definition available. + Details
Name: | ago_GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Guarantor Obligations, Net Expected Loss Development After Recoveries for Representations and Warranties, Accretion Of Discount + References No definition available. + Details
Name: | ago_GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesAccretionOfDiscount
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Guarantor Obligations, Net Expected Loss Development After Recoveries for Representations and Warranties, Changes In Discount Rates + References No definition available. + Details
Name: | ago_GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInDiscountRates
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Guarantor Obligations, Net Expected Loss Development After Recoveries for Representations and Warranties, Changes In Timing And Assumptions + References No definition available. + Details
Name: | ago_GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInTimingAndAssumptions
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Guarantor Obligations, Net Expected Loss to be Paid After Recoveries for Representations and Warranties + References No definition available. + Details
Name: | ago_GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Insured Financial Obligations, Claim Liability, Risk Free Discount Rate + References No definition available. + Details
Name: | ago_InsuredFinancialObligationsClaimLiabilityRiskFreeDiscountRate
Namespace Prefix: | ago_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Represents the period after the end of the reporting period within which the ceded paid losses are settled. + References No definition available. + Details
Name: | ago_ReinsuranceRecoverablesPeriodafterEndofReportingPeriodforSettlementofCededPaidLosses
Namespace Prefix: | ago_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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

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

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

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

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