Summary of Investments - Net Investment Gains and Losses and Proceeds (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net investment gains (losses):
Available-for-sale	$ (98)	$ 294	$ (1,397)	$ (207)
Allowance for credit losses	(91)		(91)
Allowance for credit losses		170		5
Mortgage loans allowance for credit losses	0	5	5	5
Other long-term investments	(187)	0	(229)	0
Real estate	(703)	(256)	235	(256)
Total net investment gains (losses)	(14,250)	(2,269)	(35,647)	28,243
Proceeds from sale of available-for-sale investments			83,409	170,637
Change in the fair value
Net investment gains (losses):
Equity securities	(13,078)	(1,314)	(32,403)	20,513
Sales
Net investment gains (losses):
Equity securities	(93)	(1,168)	(1,767)	8,183
Fixed maturities
Net investment gains (losses):
Proceeds from sale of available-for-sale investments	18,399	53,973	83,409	170,637
Gross realized gains	12	690	459	843
Gross realized losses	$ 110	$ 396	$ 1,857	$ 1,051

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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