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Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - New Recovery Bonds (Details) - USD ($) $ in Millions | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | $ 6,488 | $ 7,119
Fixed-maturity securities, trading | 340 | 303
Amortized Cost | 7,044 | 7,707
Gross Unrealized Gains | 51 | 65
Gross unrealized loss | (528) | (588)
Variable Interest Entity, Primary Beneficiary | Financial Guaranty Variable Interest Entities | Puerto Rico Trusts |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 218 | 204
Fixed-maturity securities, trading | 5 | 5
Amortized Cost | 205 | 204
Gross Unrealized Gains | 15 | 4
Gross unrealized loss | $ (2) | $ (4)

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