Business Reorganization (Details) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2017 employee facility	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Restructuring Reserve [Roll Forward]
Restructuring reserve		$ 0	$ 0
Employee termination benefit costs			3,796
Payments			(3,099)
Foreign currency translation			(48)
Restructuring reserve			649
Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Number of facilities eliminated | facility	2
Curtailment gain		$ 7,217	7,217
Settlement gain			230
Restructuring Reserve [Roll Forward]
Employee termination benefit costs			13
Facility Closing [Member] | Switzerland [Member]
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated | employee	60
Employee Severance
Restructuring Reserve [Roll Forward]
Employee termination benefit costs			3,796
Other Restructuring
Restructuring Reserve [Roll Forward]
Employee termination benefit costs			$ 3,664
Associated Spring Facility | Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated | employee	30