Annual report pursuant to Section 13 and 15(d)

Property, Plant and Equipment and Leased Facilities and Equipment - Summary of Property, Plant and Equipment (Details)

v3.21.1
Property, Plant and Equipment and Leased Facilities and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross $ 191,798 $ 214,996
Accumulated depreciation (124,340) (144,512)
Property, plant and equipment, net 67,458 70,484
Land    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross $ 4,972 4,972
Buildings    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 25 years  
Property, plant and equipment, gross $ 36,581 35,580
Machinery and equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 99,621 126,622
Furniture and fixtures    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 1,375 2,288
Transportation equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross $ 2,195 2,521
Improvements    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 15 years  
Property, plant and equipment, gross $ 38,934 40,377
Construction in progress    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross $ 8,120 $ 2,636
Minimum    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 3 years  
Minimum | Machinery and equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 3 years  
Minimum | Furniture and fixtures    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 3 years  
Minimum | Transportation equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 3 years  
Maximum    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 25 years  
Maximum | Machinery and equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 25 years  
Maximum | Furniture and fixtures    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 5 years  
Maximum | Transportation equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, estimated useful life 5 years