Investments - Realized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity securities
Equity securities	$ 5,056	$ 1,484	$ (819)
Net realized investment gains (losses)
Net realized investment gains (losses)	6,392	6,103	(2,010)
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	3,920	6,258	1,892
Gross realized losses	(2,585)	(1,639)	(3,189)
Net realized gains (losses) on available-for-sale securities	1,335	4,619	(1,297)
Equity securities
Equity securities
Equity securities	5,056	1,484	(819)
Miscellaneous
Net realized investment gains (losses)
Miscellaneous	$ 1	$ 0	$ 106

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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), excluding other-than-temporary impairment (OTTI).

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