Property, Plant and Equipment (Schedule of Property, Plant and Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 219,135	$ 202,293
Less: Accumulated depreciation	(131,905)	(125,629)
Property, plant and equipment, net	87,230	76,664
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment	11,970	9,920
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 90,065	82,412
Buildings and improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful Lives	5 years
Buildings and improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful Lives	20 years
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 88,806	83,445
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful Lives	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful Lives	10 years
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 10,290	8,153
Office furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful Lives	3 years
Office furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful Lives	7 years
Computer software
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 11,410	12,500
Computer software | Minimum
Property, Plant and Equipment [Line Items]
Useful Lives	3 years
Computer software | Maximum
Property, Plant and Equipment [Line Items]
Useful Lives	7 years
Transportation equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 6,594	$ 5,863
Useful Lives	3 years