Investments - Realized Investment (Losses) Gains (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Available-for-sale securities:
Net realized investment (losses) gains	$ (10,806)	$ 2,503
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	1,074	2,258
Gross realized losses	(459)	(340)
Net realized gains on available-for-sale securities	615	1,918
Equity securities
Available-for-sale securities:
Equity securities	(11,422)	585
Miscellaneous
Available-for-sale securities:
Miscellaneous	$ 1	$ 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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