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Investment Information - Net investment income (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Net investment income: |  |  |  |  |
Gross investment income |  | $ 433 | $ 422 | $ 1,269 | $ 1,158
Investment expenses |  | (25) | (23) | (78) | (68)
Net investment income |  | 408 | 399 | 1,191 | 1,090
Fixed maturities |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 379 | 340 | 1,081 | 926
Short-term investments |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 25 | 38 | 75 | 102
Equity securities |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 10 | 9 | 31 | 27
Other |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income | [1] | $ 19 | $ 35 | $ 82 | $ 103
[1] | Amounts include dividends and other distributions on investment funds, term loan investments, funds held balances, cash balances and other items.

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