Restructuring and Other Charges (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Beginning balance	$ 13,784
Restructuring and other credits	(2,438)
Cash payments	(9,246)
Effect of foreign currency translation	(58)
Ending balance	2,042
Employee Severance and Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Beginning balance	13,535
Restructuring and other credits	(2,857)
Cash payments	(9,040)
Effect of foreign currency translation	(40)
Ending balance	1,598
Excess Facilities [Member]
Restructuring Cost and Reserve [Line Items]
Beginning balance	249
Restructuring and other credits	419
Cash payments	(206)
Effect of foreign currency translation	(18)
Ending balance	$ 444