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Derivatives - CDS Spread and Components of Credit Derivative Assets (Liabilities) (Details) - USD ($) $ in Millions | Mar. 31, 2026 | Dec. 31, 2025 | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | --- | --- | ---
Credit Derivatives |  |  |  |
Fair value of credit derivatives before effect of AG credit spread | $ (40) | $ (40) |  |
Plus: Effect of AG credit spread | 24 | 25 |  |
Net fair value of credit derivatives | $ (16) | $ (15) |  |
Five-year CDS spread | AGC |  |  |  |
Credit Derivatives |  |  |  |
Quoted price of CDS contract (as a percent) | 0.78% | 0.69% | 0.90% | 0.75%
One-year CDS spread | AGC |  |  |  |
Credit Derivatives |  |  |  |
Quoted price of CDS contract (as a percent) | 0.26% | 0.23% | 0.30% | 0.25%

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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 Fair value of credit risk derivative asset after deduction of credit risk derivative liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4K -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4K + Details
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