Investments - Net Realized and Unrealized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Equity securities:
Equity securities	$ 871	$ (13,238)	$ (186)
Net realized and unrealized investment gains (losses)
Net realized and unrealized investment (losses) gains	(5,838)	(27,286)	4,946
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	804	1,169	6,884
Gross realized losses	(7,523)	(15,219)	(1,753)
Net realized (losses) gains on available-for-sale securities	(6,719)	(14,050)	5,131
Equity securities
Equity securities:
Equity securities	871	(13,238)	(186)
Miscellaneous
Net realized and unrealized investment gains (losses)
Miscellaneous	$ 10	$ 2	$ 1

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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