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Contracts Accounted for as Credit Derivatives - Credit Derivatives Subordination and Ratings (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
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Mar. 31, 2022 | Dec. 31, 2021
Credit Derivatives |  |
Estimated remaining weighted average life of credit derivatives (in years) | 13 years 4 months 24 days | 13 years 2 months 12 days
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | $ 3,574 | $ 4,040
Net Fair Value Asset (Liability) | (156) | (154)
Expected loss to be recovered | 6 | 5
Public finance | UNITED STATES |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 1,487 | 1,705
Net Fair Value Asset (Liability) | (81) | (72)
Public finance | Non United States |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 1,586 | 1,800
Net Fair Value Asset (Liability) | (46) | (48)
Structured finance | UNITED STATES |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 370 | 400
Net Fair Value Asset (Liability) | (27) | (32)
Structured finance | Non United States |  |
Net Par Outstanding on Credit Derivatives |  |
Net Par Outstanding | 131 | 135
Net Fair Value Asset (Liability) | $ (2) | $ (2)

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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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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 Average period covered by credit risk derivative contracts, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4K -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5708775-113959 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4K -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5708775-113959 + Details
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