Investments (Net Realized Investment Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Impairment losses	$ 0	$ (1,817)
Portion of impairment losses recognized in other comprehensive income before taxes:	0	654
Net impairment losses recognized in earnings	0	(1,163)
Gross realized gains, available-for-sale fixed maturities	4,294	2,427
Gross realized (losses), available-for-sale fixed maturities	(187)	(1,403)
Net realized gains (losses), trading fixed maturities	72	103
Net realized gains (losses), equity investments	4,189	15,190
Net realized gains (losses), other investments	3,196	48
Change in unrealized holding gains (losses), trading fixed maturities	(214)	(118)
Change in unrealized holding gains (losses), equity investments	(2,937)	(38,477)
Change in unrealized holding gains (losses), convertible securities, carried at fair value	(190)	(5,273)
Other	626	(7)
Total net realized investment gains (losses)	$ 8,849	$ (28,673)

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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