Summary of Investments - Net Investment Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Net investment gains (losses):
Available-for-sale	$ (797)	$ (2,662)
Allowance for credit losses	0	0
Net gains (losses) recognized on equity securities sold during the period	0	1,362
Unrealized gains (losses) recognized during the period on equity securities held at reporting date	0	0
Net gains (losses) recognized during the reporting period on equity securities	0	1,362
Mortgage loans allowance for credit losses	4	9
Other long-term investments	39	89
Total net investment gains (losses)	$ (754)	$ (1,202)

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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