Property, Plant and Equipment, Net - Summary of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Less: Accumulated depreciation	$ (217,354)	$ (206,761)
Property, plant and equipment, net	92,533	97,437
Land and Land Improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	1,095	1,095
Buildings and Improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	69,463	69,360
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	$ 239,329	$ 233,743