Summary of Investments - Net Investment Gains and Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net investment gains (losses)
Available-for-sale	$ (1,397)	$ (277)	$ 1,787
Allowance for Credit Losses	(3)		(5)
Allowance for Credit Losses		5
Mortgage loans	109	5	(4)
Other long-term assets	(267)	2,780	0
Real Estate	235	(256)	(28)
Total net investment gains (losses)	(15,892)	47,383	(32,395)
Proceeds from sales	83,559	180,514	50,744
Gross realized gains	459	843	1,400
Gross realized losses	1,857	1,120	495
Change in fair value
Net investment gains (losses)
Trading securities	0	0	(3,314)
Equity securities:	(12,802)	30,682	(6,875)
Sales
Net investment gains (losses)
Trading securities	0	0	2,950
Equity securities:	$ (1,767)	$ 14,444	$ (26,906)

Amount, excluding accrued interest, of reversal of credit loss expense on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) transferred out of available-for-sale into investment in debt security measured at amortized cost (held-to-maturity).

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