Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Total	$ 474,768	$ 466,362
Less accumulated depreciation	(318,929)	(315,010)
Net property	155,839	151,352	$ 152,755
Land
Property, Plant and Equipment [Line Items]
Total	2,929	3,573
Buildings
Property, Plant and Equipment [Line Items]
Total	114,324	110,144
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total	345,064	335,318
Construction in progress
Property, Plant and Equipment [Line Items]
Total	$ 12,451	$ 17,327