Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Total	$ 551,463	$ 531,832
Less accumulated depreciation	(384,425)	(373,892)
Property, plant and equipment, net	167,038	157,940
Land
Property, Plant and Equipment [Line Items]
Total	4,194	3,188
Buildings
Property, Plant and Equipment [Line Items]
Total	125,223	117,910
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total	397,287	386,690
Construction in progress
Property, Plant and Equipment [Line Items]
Total	$ 24,759	$ 24,044