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Relationship with Major Customers (Details) - Sales to the U.S. government
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Consolidated Revenues    
Concentration Risk [Line Items]    
Concentration percentage 40.00% 53.00%
Billed Trade Receivables    
Concentration Risk [Line Items]    
Concentration percentage 12.00% 23.00%