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Net Investment (Losses) Gains (Net Investment Gains (Losses)) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract] |  |
Fixed maturity securities, gains | $ 2,632 | $ 3,557
Fixed maturity securities, losses | (2,712) | (2,323)
Net realized (losses) gains on investment sales | (2,595) | 40,277
Change in unrealized gains | 19,947 | 25,812
Investment funds | 14 | 993
Real estate | 3,943 | (2,216)
Loans receivable | 0 | 0
Other (2) | (5,518) | (54,597)
Net realized and unrealized gains on investments in earnings before allowance for expected credit losses | 15,711 | 11,503
Fixed maturity securities | 318 | 13,882
Loans receivable | 326 | 395
Change in allowance for expected credit losses on investments | 644 | 14,277
Net investment gains | 16,355 | 25,780
Income tax expense | (3,528) | (6,633)
After-tax net investment gains | $ 12,827 | $ 19,147

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