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Contracts Accounted for as Insurance - Loss and LAE Reserve and Salvage and Subrogation Recoverable Net of Reinsurance (Details) - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
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Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Line Items] |  |
Net Reserve (Recoverable) | $ 10 | $ 75
Public finance | Financial Guarantee Insurance And Other Product Line |  |
Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Line Items] |  |
Net Reserve (Recoverable) | 101 | 120
Other structured finance | Financial Guarantee Insurance And Other Product Line |  |
Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Line Items] |  |
Net Reserve (Recoverable) | 36 | 42
Structured finance | Financial Guarantee Insurance And Other Product Line |  |
Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Line Items] |  |
Net Reserve (Recoverable) | (91) | (45)
United States | Public finance | Financial Guarantee Insurance And Other Product Line |  |
Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Line Items] |  |
Net Reserve (Recoverable) | 100 | 119
United States | RMBS | Financial Guarantee Insurance And Other Product Line |  |
Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Line Items] |  |
Net Reserve (Recoverable) | (127) | (87)
Non United States | Public finance | Financial Guarantee Insurance And Other Product Line |  |
Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Line Items] |  |
Net Reserve (Recoverable) | $ 1 | $ 1

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- Definition [Line Items] for Liability for Claims and Claims Adjustment Expense Including Salvage and Subrogation Recoverable [Table] + References No definition available. + Details
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- Definition Represents the reserve for losses and loss adjustment expenses, net of reinsurance recoverable on unpaid losses and net of salvage and subrogation recoverable. + References No definition available. + Details
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- Details
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