Investments - Realized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Available-for-sale securities:
Gross realized gains	$ 2,424	$ 604	$ 5,422	$ 3,399
Gross realized losses	(235)	(467)	(1,353)	(2,292)
Net realized gains on available-for-sale securities	2,189	137	4,069	1,107
Equity securities:
Equity securities	(579)	5,777	1,113	525
Miscellaneous:
Miscellaneous	0	1	1	3
Net realized investment gains	$ 1,610	$ 5,915	$ 5,183	$ 1,635

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

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Amount of unrealized and 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 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 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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