Investments (Major Categories of Net Investment Gains (Losses) on Investments) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Gain (Loss) on Securities [Line Items]
Gain on investments	$ 146	$ 1,403
Unrealized (losses) gain on equity investments	(95)	4,376
Investment gains, net	51	5,779
Equity Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain on equity securities	129	1,164
Corporate Bonds [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	12	197
Corporate bank loans [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	5	51
Municipal Bonds [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	$ 0	$ (9)

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of realized gain (loss) on investment in debt and equity securities.

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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).

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Amount of realized gain (loss) 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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