Restructuring Activities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($) Position
Restructuring Activities [Abstract]
Restructuring and Related Cost, Expected Number of Positions Eliminated | Position	40
Restructuring and Related Cost, Expected Cost [Abstract]
Restructuring and Related Cost, Expected Cost, Total	$ 1,999
Restructuring and Related Cost, Cost Incurred to Date	1,840
Restructuring and Related Cost, Expected Cost Remaining	159
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	498
Accruals	1,107
Payments	(1,297)
Currency translation and other adjustments	59
Restructuring Reserve, Ending Balance	367
Employee Termination Benefits [Member]
Restructuring and Related Cost, Expected Cost [Abstract]
Restructuring and Related Cost, Expected Cost, Total	831
Restructuring and Related Cost, Cost Incurred to Date	831
Restructuring and Related Cost, Expected Cost Remaining	0
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	465
Accruals	366
Payments	(503)
Currency translation and other adjustments	(11)
Restructuring Reserve, Ending Balance	317
Lease Termination Costs [Member]
Restructuring and Related Cost, Expected Cost [Abstract]
Restructuring and Related Cost, Expected Cost, Total	604
Restructuring and Related Cost, Cost Incurred to Date	604
Restructuring and Related Cost, Expected Cost Remaining	0
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	0
Accruals	604
Payments	(624)
Currency translation and other adjustments	70
Restructuring Reserve, Ending Balance	50
Assets Write-offs/Impairment [Member]
Restructuring and Related Cost, Expected Cost [Abstract]
Restructuring and Related Cost, Expected Cost, Total	222
Restructuring and Related Cost, Cost Incurred to Date	222
Restructuring and Related Cost, Expected Cost Remaining	0
Other Restructuring Costs [Member]
Restructuring and Related Cost, Expected Cost [Abstract]
Restructuring and Related Cost, Expected Cost, Total	342
Restructuring and Related Cost, Cost Incurred to Date	183
Restructuring and Related Cost, Expected Cost Remaining	159
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	33
Accruals	137
Payments	(170)
Currency translation and other adjustments	0
Restructuring Reserve, Ending Balance	$ 0