Investments (Fixed Maturities Securities Proceeds) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Proceeds from maturities/prepayments	$ 534,863	$ 410,373
Fixed maturities \| Available-for-sale
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales	106,155	60,373
Proceeds from maturities/prepayments	437,443	295,128
Gross investment gains from sales and maturities	937	2,672
Gross investment losses from sales and maturities	(8,132)	(11,938)
Write-downs recognized in earnings	0	3
(Addition to) release of allowance for credit losses	358	1,042
Noncash or part noncash divestiture, amount of consideration received	$ (8,700)	$ 54,900

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