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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 | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment losses | $ (150,455) | $ (394,832) | $ (62,476) | $ (1,365,064)
Income tax benefit | 32,090 | 79,168 | 11,626 | 288,847
Noncontrolling interests | 0 | 0 | (1) | (1)
Total change in unrealized gains | (118,365) | (315,664) | (50,851) | (1,076,218)
Debt securities |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment losses | (136,388) | (385,503) | (57,293) | (1,335,413)
Fixed maturity securities with allowance for expected credit losses |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment losses | (10,244) | (4,005) | (3,094) | (20,590)
Investment funds |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment losses | (3,217) | (5,031) | (818) | (7,863)
Other |  |  |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |  |  |
Total change in unrealized investment losses | $ (606) | $ (293) | $ (1,271) | $ (1,198)

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