Inventories (Summary of Activity within the Reserve for Excess, Obsolete, and Slow Moving Inventory) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Inventory [Roll Forward]
Beginning balance	$ 4,172	$ 3,695	$ 3,801
Excess, obsolete and slow moving inventory expense	659	729	1,276
Scrapped inventory and other adjustments	(639)	(252)	(1,382)
Ending balance	$ 4,192	$ 4,172	$ 3,695