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Net Investment (Losses) Gains (Net Investment Gains (Losses)) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Investments, Debt and Equity Securities [Abstract] |  |  |  |
Fixed maturity securities, gains | $ 4,209 | $ 3,092 | $ 6,841 | $ 6,649
Fixed maturity securities, losses | (5,654) | (5,362) | (8,366) | (7,685)
Net realized (losses) gains on investment sales | (1,100) | 61,521 | (3,695) | 101,798
Change in unrealized gains (losses) | 63,630 | (66,717) | 83,577 | (40,905)
Investment funds | 808 | 217 | 822 | 1,210
Real estate | (5,256) | (1,958) | (1,313) | (4,174)
Other (2) | (26,104) | (51,099) | (31,622) | (105,696)
Net realized and unrealized gains (losses) on investments in earnings before allowance for expected credit losses | 30,533 | (60,306) | 46,244 | (48,803)
Fixed maturity securities | 21 | 998 | 339 | 14,879
Loans receivable | 419 | 796 | 745 | 1,191
Change in allowance for expected credit losses on investments | 440 | 1,794 | 1,084 | 16,070
Net investment gains (losses) | 30,973 | (58,512) | 47,328 | (32,733)
Income tax (expense) benefit | (6,685) | 12,401 | (10,213) | 5,769
After-tax net investment gains (losses) | $ 24,288 | $ (46,111) | $ 37,115 | $ (26,964)

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