Summary of Investments - Net Investment Gains and Losses and Proceeds (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net investment gains (losses):
Available-for-sale	$ (1,632)	$ 136	$ (1,299)	$ (501)
Allowance for credit losses	0	5
Allowance for credit losses			0	(165)
Mortgage loans allowance for credit losses	0	0	5	0
Other long-term investments	(22)	0	(42)	0
Real estate	938	0	938	0
Total net investment gains (losses)	(20,932)	6,004	(21,397)	30,512
Proceeds from sale of available-for-sale investments			65,010	116,664
Fixed maturities
Net investment gains (losses):
Proceeds from sale of available-for-sale investments	65,010	16,982	65,010	116,664
Gross realized gains	114	152	447	153
Gross realized losses	1,747	17	1,747	655
Change in the fair value
Net investment gains (losses):
Equity securities	(18,335)	1,245	(19,324)	21,827
Sales
Net investment gains (losses):
Equity securities	$ (1,881)	$ 4,618	$ (1,675)	$ 9,351

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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