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Net Investment (Losses) Gains (Net Investment Gains (Losses)) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract] |  |  |  |
Fixed maturity securities, gains | $ 4,799 | $ 299 | $ 11,448 | $ 1,357
Fixed maturity securities, losses | (3,884) | (2,700) | (11,569) | (24,470)
Net realized gains on investment sales (2) | 407 | 23,631 | 102,205 | 135,763
Change in unrealized (losses) gains | (1,537) | (19,059) | (42,442) | 45,605
Investment funds | (101) | (3,329) | 1,109 | (3,417)
Real estate (3) | 1,470 | (24,234) | (2,704) | (68,944)
Loans receivable | 0 | (1,428) | 0 | (1,428)
Other (4) | (24,516) | (14,035) | (130,212) | (34,063)
Net realized and unrealized (losses) gains on investments in earnings before allowance for expected credit losses | (23,362) | (40,855) | (72,165) | 50,403
Fixed maturity securities | 14,888 | (2,112) | 29,768 | (8,946)
Loans receivable | 388 | 541 | 1,579 | (2,218)
Change in allowance for expected credit losses on investments | 15,276 | (1,571) | 31,347 | (11,164)
Net investment (losses) gains | (8,086) | (42,426) | (40,818) | 39,239
Income tax benefit (expense) | $ 43 | 9,405 | $ 5,810 | (8,033)
After-tax net investment (losses) gains |  | $ (33,021) |  | $ 31,206

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