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Contracts Accounted for as Credit Derivatives - Credit Derivatives Net Par Outstanding by Sector (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | $ 3,608 | $ 3,203
Net Fair Value Asset (Liability) | (50) | (162)
Expected Loss to be recovered | 2 | 3
Public finance | U.S. |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 1,149 | 1,175
Net Fair Value Asset (Liability) | (15) | (79)
Public finance | Non U.S. |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 1,522 | 1,565
Net Fair Value Asset (Liability) | (20) | (58)
Structured finance | U.S. |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 322 | 342
Net Fair Value Asset (Liability) | (13) | (22)
Structured finance | Non U.S. |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 615 | 121
Net Fair Value Asset (Liability) | $ (2) | $ (3)

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- Definition Expected Loss on Credit Derivative to Be Paid (Recovered), Including Representation and Warranty Liability (Benefit) + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- References No definition available. + Details
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- Definition Represents the outstanding principal amounts of the underlying insured obligations that are accounted for as credit derivatives, net of protection purchased. + References No definition available. + Details
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- Definition Fair value of credit risk derivative asset after deduction of credit risk derivative liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4K -Subparagraph (c) -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4K + Details
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