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Contracts Accounted for as Credit Derivatives - Distribution of Credit Derivative Net Par Outstanding by Internal Rating (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2022 | Dec. 31, 2021
Credit Derivatives |  |
Net Par Outstanding | $ 3,301 | $ 4,040
BIG |  |
Credit Derivatives |  |
Net Par Outstanding | 59 | 63
Credit Concentration Risk | Derivative, Aggregate Notional Amount |  |
Credit Derivatives |  |
Net Par Outstanding | $ 3,301 | $ 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 | $ 1,317 | $ 1,503
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 39.90% | 37.20%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | AA |  |
Credit Derivatives |  |
Net Par Outstanding | $ 1,116 | $ 1,283
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 33.80% | 31.80%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | A |  |
Credit Derivatives |  |
Net Par Outstanding | $ 329 | $ 514
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 10.00% | 12.70%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | BBB |  |
Credit Derivatives |  |
Net Par Outstanding | $ 480 | $ 677
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 14.50% | 16.70%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | BIG |  |
Credit Derivatives |  |
Net Par Outstanding | $ 59 | $ 63
Percentage of installment premiums denominated in currencies other than the U.S. dollar | 1.80% | 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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