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Contracts Accounted for as Credit Derivatives - CDS Spread and Components of Credit Derivative Assets (Liabilities) (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023
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Credit Derivatives |  |  |  |
Fair value of credit derivatives before effect of AG credit spread | $ (67) | $ (64) |  |
Plus: Effect of AG credit spread | 37 | 35 |  |
Net fair value of credit derivatives | $ (30) | $ (29) |  |
Five-year CDS spread | AGC |  |  |  |
Credit Derivatives |  |  |  |
Quoted price of CDS contract (as a percent) | 9000.00% | 7500.00% | 0.52% | 0.66%
One-year CDS spread | AGC |  |  |  |
Credit Derivatives |  |  |  |
Quoted price of CDS contract (as a percent) | 3000.00% | 2500.00% | 0.19% | 0.23%

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- Definition Represents the quoted price of credit derivative contracts. + References No definition available. + Details
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- Definition Fair value before effect of credit spread as of the balance sheet date of credit risk derivative assets, net of credit risk derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet. + References No definition available. + 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 -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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- Definition Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity. + References No definition available. + Details
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