Investments - Realized and Unrealized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Available-for-sale securities:
Gross realized gains	$ 491	$ 1,923
Gross realized losses	(2,571)	(440)
Net realized (losses) gains on available-for-sale securities	(2,080)	1,483
Equity securities:
Equity securities	(5,201)	(679)
Miscellaneous:
Miscellaneous	2	0
Net realized and unrealized investment (losses) gains	$ (7,279)	$ 804

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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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