Investments (Net Realized Investment Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Impairment losses	$ (1,817)	$ (136)
Portion of impairment losses recognized in other comprehensive income (loss) before taxes	654	87
Net impairment losses recognized in earnings	(1,163)	(49)
Gross realized gains, available-for-sale fixed maturities	2,427	367
Gross realized (losses), available-for-sale fixed maturities	(1,403)	(336)
Net realized gains (losses), trading fixed maturities	103	(28)
Net realized gains (losses), equity investments	15,190	1,790
Net realized gains (losses), other investments	48	379
Change in unrealized holding gains (losses), trading fixed maturities	(118)	210
Change in unrealized holding gains (losses), equity investments	(38,477)	32,394
Change in unrealized holding gains (losses), convertible securities, carried at fair value	(5,273)	1,895
Other	(7)	1
Total net realized investment gains (losses)	$ (28,673)	$ 36,623

Impairment Loss, Debt Securities, Portion Recognized in Earnings

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Impairment Losses, Investments

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Impairment Losses, Investments, Portion In Other Comprehensive Loss, Before Tax, Portion Attributable To Parent

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This item represents the gain (loss) realized during the period from the sale of Other Investments.

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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 gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of realized gain from sale of 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 the unrealized gain (loss) in earnings for the period from the increase (decrease) in fair value on hybrid instruments measured at fair value.

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