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Net Investment Gains (Losses) (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Realized and Unrealized Investment Gains Losses [Line Items] |  |
Total change in unrealized investment losses | $ (539,449) | $ (113,735)
Income tax benefit | 115,904 | 23,605
Noncontrolling interests | (1) | 0
Total change in unrealized gains | (423,546) | (90,130)
Debt securities |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |
Total change in unrealized investment losses | (540,263) | (122,568)
Fixed maturity securities with allowance for expected credit losses |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |
Total change in unrealized investment losses | 293 | 10,355
Investment funds |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |
Total change in unrealized investment losses | 469 | (1,020)
Other |  |
Realized and Unrealized Investment Gains Losses [Line Items] |  |
Total change in unrealized investment losses | $ 52 | $ (502)

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