Investments (Major Categories of Net Investment Gains (Losses) on Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Gain (Loss) on Securities [Line Items]
Gain on investments	$ 6,046	$ 2,125
Other-than-temporary impairment	0	(1,692)
Investment (losses) gains, net	10,222	(22,894)
Equity Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain on equity securities	5,453	3,472
Unrealized (losses) gains	4,176	(24,921)
Other Investments [Member]
Gain (Loss) on Securities [Line Items]
Gain on equity securities	0	(3,740)
Unrealized (losses) gains	0	1,594
U.S. Treasury securities and obligations of U.S. Government [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	0	(3)
Corporate Bonds [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	494	959
Corporate bank loans [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	124	40
Municipal Bonds [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	(25)	1,397
Collateralized Mortgage Backed Securities [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	$ 0	$ 0

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 security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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