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Net Investment (Losses) Gains (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment (losses) gains | $ (20,640) | $ (144,043) | $ (109,937) | $ 87,978
Income tax benefit (expense) | 7,302 | 30,759 | 26,477 | (20,463)
Noncontrolling interests | 1 | 0 | 1 | (1)
Total change in unrealized gains | (13,337) | (113,284) | (83,459) | 67,514
Debt securities |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment (losses) gains | (11,394) | (148,021) | (99,988) | 79,094
Fixed maturity securities with allowance for expected credit losses |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment (losses) gains | (7,683) | 3,694 | (6,696) | 7,150
Investment funds |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment (losses) gains | (1,338) | 462 | (3,041) | 2,398
Other |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment (losses) gains | $ (225) | $ (178) | $ (212) | $ (664)

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