Inventories (Summary of Activity within the Reserve for Excess, Obsolete, and Slow Moving Inventory) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Inventory [Roll Forward]
Beginning balance	$ 3,463	$ 2,971	$ 2,852
Excess, obsolete and slow moving inventory expense	355	1,134	363
Scrapped inventory and other adjustments	(343)	642	244
Ending balance	$ 4,161	$ 3,463	$ 2,971