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Investment Information - Net investment income (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Net investment income: |  |  |
Gross investment income |  | $ 219 | $ 103
Investment expenses |  | (20) | (23)
Net investment income |  | 199 | 80
Fixed maturities |  |  |
Net investment income: |  |  |
Gross investment income |  | 188 | 82
Term loans |  |  |
Net investment income: |  |  |
Gross investment income |  | 0 | 2
Equity securities |  |  |
Net investment income: |  |  |
Gross investment income |  | 4 | 6
Short-term investments |  |  |
Net investment income: |  |  |
Gross investment income |  | 14 | 3
Other |  |  |
Net investment income: |  |  |
Gross investment income | [1] | $ 13 | $ 10
[1] | Includes income distributions from investment funds and other items.

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