Investments (Major Categories of Net Investment Gains (Losses) on Investments) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	$ 0
Gain on equity securities	624	$ 129
(Loss) Gain on investments	(610)	146
Unrealized (losses) gains on equity securities	(30)	(95)
Investment gains, net	(640)	51
U.S. Treasury securities and obligations of U.S. Government [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	(22)
Corporate bonds [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	(1,117)	12
Corporate bank loans [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	(91)	$ 5
Municipal bonds [Member]
Gain (Loss) on Securities [Line Items]
Gain (loss) on debt securities	$ (4)

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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