Investments - Realized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Available-for-sale securities:
Net realized investment gains	$ 5,915	$ 1,696	$ 1,635	$ 5,501
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	604	1,320	3,399	5,640
Gross realized losses	(467)	(248)	(2,292)	(1,411)
Net realized gains on available-for-sale securities	137	1,072	1,107	4,229
Equity securities
Available-for-sale securities:
Equity securities	5,777	624	525	1,272
Miscellaneous
Available-for-sale securities:
Miscellaneous	$ 1	$ 0	$ 3	$ 0

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

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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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