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Net Investment (Losses) Gains (Net Investment Gains (Losses)) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract] |  |
Fixed maturity securities, gains | $ 3,557 | $ 943
Fixed maturity securities, losses | (2,323) | (18,130)
Net realized gains on investment sales | 40,277 | 1,060
Change in unrealized gains | 25,812 | 43,404
Investment funds | 993 | 10
Real estate | (2,216) | 10,739
Loans receivable | 0 | 0
Other (2) | (54,597) | (15,415)
Net realized and unrealized gains on investments in earnings before allowance for expected credit losses | 11,503 | 22,611
Fixed maturity securities | 13,882 | 217
Loans receivable | 395 | 182
Change in allowance for expected credit losses on investments | 14,277 | 399
Net investment gains | 25,780 | 23,010
Income tax expense | (6,633) | (4,850)
After-tax net investment gains | $ 19,147 | $ 18,160

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