Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Land	$ 4,712	$ 4,736
Buildings and improvements	54,448	54,362
Machinery and equipment	190,316	189,428
Construction in progress	1,437	224
Property, Plant and Equipment, Gross	250,913	248,750
Less: accumulated depreciation	(178,093)	(173,465)
Total property, plant and equipment, net	$ 72,820	$ 75,285
Minimum [Member] | Building and Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Minimum [Member] | Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	2 years
Maximum [Member] | Building and Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Maximum [Member] | Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	25 years