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v3.25.1

Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Additional Information (Details) | Mar. 31, 2025 USD ($) Entity policy | Dec. 31, 2024 USD ($) Entity policy | Mar. 31, 2024 USD ($)
--- | --- | --- | ---
Variable Interest Entity [Line Items] |  |  |
Assets | $ 11,938,000,000 | $ 11,901,000,000 |
Cash | $ 177,000,000 | $ 121,000,000 | $ 115,000,000
Number of policies monitored | policy | 15,000 |  |
Number of policies monitored, not within the scope of ASC 810 | policy | 14,000 |  |
Number of policies that contain provisions for consolidation | policy | 50 | 50 |
Net fair value gains and losses on FG VIEs are expected to reverse to zero at maturity of the VIE debt | $ 766,000,000 |  |
Financial Guaranty Variable Interest Entities | Variable Interest Entity, Primary Beneficiary |  |  |
Variable Interest Entity [Line Items] |  |  |
Maximum loss exposure | $ 0 |  |
Financial Guaranty Variable Interest Entities | Variable Interest Entity, Primary Beneficiary | Structured finance |  |  |
Variable Interest Entity [Line Items] |  |  |
Number of entities | Entity | 23 | 23 |
Consolidated Investment Vehicles | Variable Interest Entity, Primary Beneficiary |  |  |
Variable Interest Entity [Line Items] |  |  |
Total number of entities consolidated | Entity | 1 | 1 |
Assets | $ 119,000,000 | $ 101,000,000 |
Cash | 1,000,000 | 2,000,000 |
Consolidated Investment Vehicles | Variable Interest Entity, Primary Beneficiary | Affiliated Entity |  |  |
Variable Interest Entity [Line Items] |  |  |
Assets | $ 118,000,000 | $ 99,000,000 |

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