Summary of Investments - Net Investment Gains and Losses and Proceeds (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net investment gains (losses):
Available-for-sale	$ (248)	$ (1,632)	$ (426)	$ (1,299)
Allowance for credit losses	177	0	1	0
Mortgage loans allowance for credit losses	(6)	0	(6)	5
Other long-term investments	(122)	(22)	(308)	(42)
Real estate	47	938	47	938
Total net investment gains (losses)	1,124	(20,932)	(621)	(21,397)
Proceeds from sales			43,809	65,010
Change in the fair value
Net investment gains (losses):
Equity securities	(459)	(18,335)	(2,164)	(19,324)
Sales
Net investment gains (losses):
Equity securities	1,735	(1,881)	2,235	(1,675)
Fixed maturities
Net investment gains (losses):
Proceeds from sales	33,941	65,010	43,809	65,010
Gross realized gains	110	114	121	447
Gross realized losses	$ 358	$ 1,747	$ 547	$ 1,747

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with previously recorded allowance and not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis.

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