Other Income (Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Income and Expenses [Abstract]
Accrual for loss contingency related to legal proceedings (see Footnote 8)									$ 0	$ 0	$ (5,000)
Recovery of INOVA bad debts									0	0	844
Other income (expense)									(1,617)	(436)	211
Total other expense, net	$ (679)	$ (242)	$ 96	$ (792)	$ 180	$ 91	$ 84	$ (791)	$ (1,617)	$ (436)	$ (3,945)