Investments - Net Realized and Unrealized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Equity securities:
Equity securities	$ 244	$ (1,624)	$ (3,060)	$ (14,727)
Net realized and unrealized investment gains (losses)
Net realized and unrealized investment losses	(2,227)	(6,230)	(9,246)	(23,833)
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	213	146	519	1,055
Gross realized losses	(2,693)	(4,752)	(6,714)	(10,163)
Net realized losses on available-for-sale securities	(2,480)	(4,606)	(6,195)	(9,108)
Equity securities
Equity securities:
Equity securities	244	(1,624)	(3,060)	(14,727)
Miscellaneous
Net realized and unrealized investment gains (losses)
Miscellaneous	$ 9	$ 0	$ 9	$ 2

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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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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of gain (loss) included in earnings for investments classified as other.

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