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Investments and Cash - Net Investment Income (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Net Investment Income |  |  |
Gross investment income | $ 345 | $ 370 | $ 274
Investment expenses | (5) | (5) | (5)
Net investment income | 340 | 365 | 269
Fair value gains (losses) on trading securities | 52 | 74 | (34)
Equity in earnings (losses) of investees | 62 | 28 | (39)
Fair value of gain (loss) on trading securities still held | $ 15 | 31 | (29)
Fair Value, Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Fair value gains (losses) on trading securities |  |
Fixed-maturity securities. available-for-sale |  |  |
Net Investment Income |  |  |
Gross investment income | $ 261 | 294 | 258
Short-term investments |  |  |
Net Investment Income |  |  |
Gross investment income | 83 | 73 | 15
Other |  |  |
Net Investment Income |  |  |
Gross investment income | 1 | 3 | 1
Sound Point |  |  |
Net Investment Income |  |  |
Equity in earnings (losses) of investees | 6 | 5 | 0
Equity Funds |  |  |
Net Investment Income |  |  |
Equity in earnings (losses) of investees | 56 | 23 | (39)
Loss mitigation securities |  |  |
Net Investment Income |  |  |
Gross investment income | $ 28 | $ 55 | $ 31

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