Investments (Narrative) (Details) - USD ($) $ in Thousands		1 Months Ended		3 Months Ended			9 Months Ended
	Sep. 25, 2017	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Apr. 12, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Shares issued in debt-for-equity exchange (in shares)		500,000	2,300,000	500,000			2,800,000
Cash tender offer (maximum)				$ 22,300			$ 112,300
Shares held		1,200,000		1,200,000			1,200,000
Impairment loss on equity securities						$ 16,700
Fair Value		$ 15,000		$ 15,000			$ 15,000
Variable interest entity, amount committed to invest	$ 200,000
Annual management fee percentage	2.00%
Entitled carried interest percentage	20.00%
Investment period	6 years
Equity securities		109,228		109,228			109,228			$ 122,593
Variable interest entity, amount of capital call notices received							0	$ 21,200
Variable interest entity, amount paid								21,200
Distribution from equity method investment							0	15,327
Income (loss) from equity method investment				(3,191)	$ (1,923)		(10,077)	16,596
Management fees recognized				0	$ 800		1,500	2,300
OCV Management, LLC
Debt Securities, Available-for-sale [Line Items]
Distribution from equity method investment							0	$ 0
Investment in corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, coupon rate									4.00%
Fair Value		$ 15,000		$ 15,000			$ 15,000		$ 15,000
Ownership interest									3.00%
Fund
Debt Securities, Available-for-sale [Line Items]
Equity securities	$ 128,800
Individually Insignificant Equity Securities
Debt Securities, Available-for-sale [Line Items]
Ownership percentage	76.60%