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Investments and Cash - Investment Portfolio Carrying Value (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Schedule of Cost-method Investments [Line Items] |  |
Fixed-maturity securities, available-for-sale | $ 6,369 | $ 6,307
Fixed-maturity securities, trading | 147 | 318
Short-term investments | 1,221 | 1,661
Other invested assets: |  |
Other invested assets | 926 | 829
Total investments | 8,663 | 9,115
Sound Point |  |
Other invested assets: |  |
Equity method investments | 418 | 429
Total investments | 569 | 202
Funds and other investments |  |
Other invested assets: |  |
Other invested assets | 496 | 394
Other |  |
Other invested assets: |  |
Other invested assets | $ 12 | $ 6

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