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Investments (Major Categories of Net Investment Gains (Losses) on Investments) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities			$ 0	$ 600
Gain on investments	$ 504	$ 1,059	1,667	5,288
Unrealized (losses) gain on equity investments	(3,325)	(1,592)	(8,431)	3,834
Investment gains, net	(2,821)	(533)	(6,764)	9,122
Equity Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain on equity securities		930	1,141	4,701
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	300		300
Corporate bonds [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	160	133	172	494
Corporate bank loans [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	39	14	66	105
Municipal bonds [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	(4)	$ (18)	$ (12)	$ (12)
Mortgage-backed [Member] \| Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	$ 9