Investments (Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at fair value	$ 10,555		$ 10,555		$ 11,590
Investment related gains (losses), net	(892)	$ (4,991)	(477)	$ (10,589)
Stock Mutual Funds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at fair value	2,034		2,034		2,615
Bond Mutual Funds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at fair value	4,196		4,196		4,337
Common stock [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at fair value	622		622		857
Non-redeemable Preferred Stock [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at fair value	8		8		8
Nonredeemable Preferred Stock Fund Member [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at fair value	3,695		3,695		$ 3,773
Equity Securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Investment related gains (losses), net	$ (400)	$ (900)	$ (300)	$ (2,900)