Investments - Realized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Available-for-sale securities:
Gross realized gains	$ 1,075	$ 1,721	$ 2,998	$ 2,795
Gross realized losses	(678)	(1,366)	(1,118)	(1,825)
Net realized gains on available-for-sale securities	397	355	1,880	970
Equity securities:
Equity securities	2,371	6,170	1,692	(5,252)
Miscellaneous:
Miscellaneous	1	1	1	2
Net realized investment gains (losses)	$ 2,769	$ 6,526	$ 3,573	$ (4,280)

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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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