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Contracts Accounted for as Credit Derivatives - Distribution of Credit Derivative Net Par Outstanding by Internal Rating (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Credit Derivatives |  |
Net Par Outstanding | $ 3,574 | $ 4,040
BIG |  |
Credit Derivatives |  |
Net Par Outstanding | 60 | 63
Credit Concentration Risk | Derivative, Aggregate Notional Amount |  |
Credit Derivatives |  |
Net Par Outstanding | $ 3,574 | $ 4,040
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 100.00% | 100.00%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | AAA |  |
Credit Derivatives |  |
Net Par Outstanding | $ 1,359 | $ 1,503
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 38.00% | 37.20%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | AA |  |
Credit Derivatives |  |
Net Par Outstanding | $ 1,217 | $ 1,283
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 34.10% | 31.80%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | A |  |
Credit Derivatives |  |
Net Par Outstanding | $ 407 | $ 514
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 11.40% | 12.70%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | BBB |  |
Credit Derivatives |  |
Net Par Outstanding | $ 531 | $ 677
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 14.80% | 16.70%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | BIG |  |
Credit Derivatives |  |
Net Par Outstanding | $ 60 | $ 63
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 1.70% | 1.60%

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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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