Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 53,678	$ 52,969
Less accumulated depreciation	(33,132)	(31,921)
Total property and equipment	20,546	21,048
Land [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,565	1,565
Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	18,082	17,834
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	31,959	31,707
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	778	778
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	895	857
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 399	$ 228