Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment
Property, Plant and Equipment	$ 276,811	$ 262,214
Accumulated Depreciation	(181,853)	(175,671)
Property, Plant and Equipment, Net	94,958	86,543
Accumulated Depreciation, Property, Plant and Equipment prior to Assets Held for Sale	183,849	175,671
Impairment loss recorded on fixed assets	622
Depreciation expense	16,550	17,694	$ 17,686
Land
Property, Plant and Equipment
Property, Plant and Equipment	4,232	4,265
Buildings and improvements
Property, Plant and Equipment
Property, Plant and Equipment	52,118	52,962
Machinery and manufacturing equipment
Property, Plant and Equipment
Property, Plant and Equipment	117,197	117,622
Office equipment
Property, Plant and Equipment
Property, Plant and Equipment	80,972	73,677
Work in progress
Property, Plant and Equipment
Property, Plant and Equipment	24,481	13,688
Gross Property, Plant and Equipment held for sale
Property, Plant and Equipment
Property, Plant and Equipment	(2,189)	0
Accumulated Depreciation, reduction due to assets held for sale	$ 1,996	$ 0