Schedule II - Valuation and Qualifying Accounts - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
Beginning Balance	$ 1,725	$ 2,640
Additions/ Charged to Expenses	618	(918)
Currency Impact	(76)	134
Reductions	(104)	(131)
Balance at End of Period	2,163	1,725
Tax Valuation Allowance [Member]
Beginning Balance	8,647	11,068
Additions/ Charged to Expenses	1,616
Currency Impact
Reductions		(2,421)
Balance at End of Period	10,263	8,647
SEC Schedule, 12-09, Reserve, Inventory [Member]
Beginning Balance	59	435
Additions/ Charged to Expenses	(46)	(287)
Currency Impact		23
Reductions	(3)	(112)
Balance at End of Period	$ 10	$ 59