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Industry, Geographic, and Revenue Disaggregation - Narrative (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2019
USD ($)
segment
Dec. 31, 2018
USD ($)
Dec. 31, 2017
Segment Reporting [Abstract]      
Number of operating segments | segment 1    
Concentration Risk [Line Items]      
Trade accounts receivable $ 3,222 $ 1,860  
Lease income $ 1,300    
Total Revenue | One Customer      
Concentration Risk [Line Items]      
Risk concentration 28.00% 27.00% 28.00%
Accounts Receivable | Geographic Concentration | Outside the U.S.      
Concentration Risk [Line Items]      
Trade accounts receivable $ 2,100 $ 900