Supplemental Balance Sheet Information - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 315,221	$ 358,226
Less – Accumulated depreciation	(206,181)	(201,479)
Property, Plant and Equipment, Net	109,040	156,747
Depreciation	29,300	30,400	$ 30,600
Land and land improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	10,258	10,414
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 47,725	65,505
Buildings and improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	5 years
Buildings and improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	40 years
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 159,626	189,849
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	4 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	10 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 35,149	32,386
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	3 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	10 years
Autos and trucks
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 54,039	50,128
Autos and trucks | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	3 years
Autos and trucks | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives (Years)	10 years
Construction in progress
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 8,424	$ 9,944