Summary of Investments - Net Investment Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Net investment gains (losses):
Available-for-sale	$ (2,662)	$ (178)
Allowance for credit losses	0	(176)
Net gains (losses) recognized on equity securities sold during the period	1,362	500
Unrealized gains (losses) recognized during the period on equity securities held at reporting date	0	(1,705)
Net gains (losses) recognized during the reporting period on equity securities	1,362	(1,205)
Mortgage loans allowance for credit losses	9	0
Other long-term investments	89	(186)
Real estate	0	0
Total net investment gains (losses)	(1,202)	(1,745)
Proceeds from sales	88,378	9,868
Gross realized gains	1,365	11
Gross realized losses	$ 4,027	$ 189

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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