Fair Value Measurement and Fair Value of Financial Instruments (Reconciliation of Assets and Liabilities Measured on Recurring Basis) (Details) - Fair Value, Measurements, Recurring - Significant Unobservable Inputs (Level 3) - Equity contracts - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Reconciliation of the beginning and ending balances for warrants issued by private companies measured at fair value on a recurring basis using significant unobservable inputs (Level 3)
Beginning balance	$ 215	$ 273
Total gains (losses) included in earnings	3	(1)
Issuances	91	0
Ending balance	$ 309	$ 272