Costs Associated with Exit and Restructuring Activities - Restructuring Reserve Activity (Details 3) $ in Thousands	12 Months Ended			21 Months Ended	31 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 position	Dec. 31, 2018 USD ($) position
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 5,062	$ 4,139	$ 3,048
Restructuring reserve activity
Restructuring Reserve, Current	1,586				$ 1,586
June2016 Plan
Restructuring Cost and Reserve [Line Items]
Elimination of workforce | position					230
Restructuring reserve activity
Restructuring liability at ending	668				$ 668
April 2014 Plan and June 2016 Plan
Restructuring reserve activity
Restructuring liability at beginning	1,913
Restructuring and restructuring-related charges	5,062
Cost paid	(5,465)
Restructuring Reserve, Translation and Other Adjustment	76
Restructuring liability at ending	1,586	1,913			1,586
April 2014 Plan
Restructuring Cost and Reserve [Line Items]
Elimination of workforce | position				120
Restructuring Charges	503	0	4,923
Restructuring and Related Cost, Expected Cost	9,950				9,950
Restructuring reserve activity
Restructuring liability at ending	918				918
Operating Expense | June2016 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	4,559	$ 4,139	$ 3,048
Restructuring and Related Cost, Expected Cost	13,400				13,400
Operating Expense | April 2014 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	5,900				5,900
Workforce reduction | Operating Expense | June2016 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	3,075				3,075
Workforce reduction | Operating Expense | April 2014 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	4,200				4,200
Equipment relocation | Operating Expense | June2016 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	9,025				9,025
Other charges | Operating Expense | June2016 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	$ 1,300				$ 1,300