Income Taxes (Income Tax Provision (Benefit)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal									$ 0	$ 0	$ 0
State									45	(42)	(119)
Foreign									847	2,762	1,806
Total									892	2,720	1,687
Deferred:
Federal									101	(1,189)	898
State									238	(3,992)	1,060
Foreign									(329)	1,454	61
Total									10	(3,727)	2,019
Income tax provision (benefit)	$ 1,740	$ 241	$ (664)	$ (415)	$ 1,733	$ 552	$ (4,463)	$ 1,171	$ 902	$ (1,007)	$ 3,706