Supplemental Balance Sheet Information - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 309,095	$ 315,221
Less – Accumulated depreciation	(202,036)	(206,181)
Property, Plant and Equipment, Net	107,059	109,040
Depreciation	23,900	29,300	$ 30,400
Land and land improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	10,521	10,258
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 47,430	47,725
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	$ 147,918	159,626
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	$ 37,471	35,149
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	$ 51,129	54,039
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	$ 14,626	$ 8,424