Revenue from Contracts with Customers (Details 3) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Deferred Revenue, Current		$ 5,064	$ 5,304
Deferred Revenue, Noncurrent		3,140	2,483
Movement in Deferred Revenue [Roll Forward]
Beginning balance	$ 7,787
Increase in deferred revenue representing our obligation to satisfy future performance obligations	11,032
Decrease in deferred revenue for amounts recognized in Net Sales for satisfied performance obligations	(10,475)
Foreign currency fluctuations	(140)
Ending balance	8,204
Revenue, Performance Obligation Satisfied over Time [Abstract]
Remaining 2018		2,502
2019		2,958
2020		1,595
2021		692
2022		381
Thereafter		76
Total	$ 7,787	$ 8,204	$ 7,787
Prepaid Maintenance Contract Duration, Minimum
Disaggregation of Revenue [Line Items]
Standard Prepaid Maintenance Contract Time Period	12 months
Prepaid Maintenance Contract Duration, Maximum
Disaggregation of Revenue [Line Items]
Standard Prepaid Maintenance Contract Time Period	60 months