Annual report pursuant to Section 13 and 15(d)

Permit and Other Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details)

v3.21.1
Permit and Other Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Gross Carrying Amount $ 4,530 $ 5,089
Accumulated Amortization (3,655) (4,024)
Finite-Lived Intangible Assets, Net $ 875 1,065
Patent [Member]    
Weighted Average Amortization Period (Years) 13 years  
Gross Carrying Amount $ 742 760
Accumulated Amortization (334) (358)
Finite-Lived Intangible Assets, Net $ 408 402
Software [Member]    
Weighted Average Amortization Period (Years) 3 years  
Gross Carrying Amount $ 418 414
Accumulated Amortization (411) (408)
Finite-Lived Intangible Assets, Net $ 7 6
Customer Relationships [Member]    
Weighted Average Amortization Period (Years) 10 years  
Gross Carrying Amount $ 3,370 3,370
Accumulated Amortization (2,910) (2,713)
Finite-Lived Intangible Assets, Net 460 657
Permit [Member]    
Gross Carrying Amount 545
Accumulated Amortization (545)
Finite-Lived Intangible Assets, Net