Summary of Investments - Net Investment Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Net investment gains (losses):
Available-for-sale	$ (1,382)	$ (248)	$ (4,044)	$ (426)
Allowance for credit losses	1	177	1	1
Net gains (losses) recognized on equity securities sold during the period	0	1,735	1,362	2,235
Unrealized gains (losses) recognized during the period on equity securities held at reporting date	0	(459)	0	(2,164)
Net gains (losses) recognized during the reporting period on equity securities	0	1,276	1,362	71
Mortgage loans allowance for credit losses	0	(6)	10	(6)
Other long-term investments	152	(122)	241	(308)
Real estate	0	47	0	47
Total net investment gains (losses)	$ (1,229)	$ 1,124	$ (2,431)	$ (621)

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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