Property, Plant and Equipment - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, at cost	$ 51,220	$ 49,667
Accumulated depreciation	(30,104)	(26,473)
Property, plant and equipment, net	21,116	23,194
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, at cost	6,820	6,745
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, at cost	42,857	41,243
Construction in progress
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, at cost	$ 1,543	$ 1,679