Investments - Net Realized and Unrealized Investment (Losses) Gains (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Equity securities:
Net (losses) gains recognized during the period	$ (13,238)	$ (186)	$ 5,056
Net realized investment gains
Net realized and unrealized investment (losses) gains	(27,286)	4,946	6,392
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	1,169	6,884	3,920
Gross realized losses	(15,219)	(1,753)	(2,585)
Net realized (losses) gains on available-for-sale securities	(14,050)	5,131	1,335
Equity securities
Equity securities:
Net (losses) gains recognized during the period	(13,238)	(186)	5,056
Miscellaneous
Net realized investment gains
Miscellaneous	$ 2	$ 1	$ 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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