Investments - Net Realized and Unrealized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Equity securities:
Equity securities	$ 359	$ (7,902)	$ (3,304)	$ (13,103)
Net realized and unrealized investment gains (losses)
Net realized and unrealized investment losses	(1,737)	(10,324)	(7,019)	(17,603)
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	100	418	306	909
Gross realized losses	(2,196)	(2,840)	(4,021)	(5,411)
Net realized losses on available-for-sale securities	(2,096)	(2,422)	(3,715)	(4,502)
Equity securities
Equity securities:
Equity securities	359	(7,902)	(3,304)	(13,103)
Miscellaneous
Net realized and unrealized investment gains (losses)
Miscellaneous	$ 0	$ 0	$ 0	$ 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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