Summary of Investments - Net Investment Gains and Losses and Proceeds (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Net investment gains (losses):
Available-for-sale	$ (178)	$ 333
Allowance for credit losses	(176)
Allowance for credit losses		0
Mortgage loans allowance for credit losses	0	5
Other long-term investments	(186)	(20)
Total net investment gains (losses)	(1,745)	(465)
Proceeds from sales	9,868	0
Change in the fair value
Net investment gains (losses):
Equity securities	(1,705)	(989)
Sales
Net investment gains (losses):
Equity securities	500	206
Fixed maturities
Net investment gains (losses):
Proceeds from sales	9,868	0
Gross realized gains	11	333
Gross realized losses	$ 189	$ 0

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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