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Net Investment Income | 12 Months Ended
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Dec. 31, 2023
Net Investment Income [Abstract] |
Net Investment Income | Net Investment Income Net investment income consists of the following:
(In thousands) | 2023 |  | 2022 |  | 2021
Investment income (loss) earned on: |  |  |  |  |
Fixed maturity securities, including cash and cash equivalents and loans receivable | $ | 929,098 |  |  | $ | 549,281 |  |  | $ | 382,001 |
Arbitrage trading account (1) | 69,369 |  |  | 45,213 |  |  | 37,676 |
Equity securities | 55,726 |  |  | 52,600 |  |  | 32,020 |
Investment funds | 16,743 |  |  | 145,099 |  |  | 220,014 |
Real estate | (11,185) |  |  | (3,087) |  |  | 7,703 |
Gross investment income | 1,059,751 |  |  | 789,106 |  |  | 679,414 |
Investment expense | (6,916) |  |  | (9,921) |  |  | (7,796) |
Net investment income | $ | 1,052,835 |  |  | $ | 779,185 |  |  | $ | 671,618 |

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