Restructuring Charges (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		$ 800	$ 6,700
Other Restructuring Costs	$ 200
Business Restructuring Reserves [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			4,200
Special Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Buy-out agreement		0
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		$ 600	$ 1,900