XML 64 R50.htm IDEA: XBRL DOCUMENT v3.19.1
Unbilled Accounts Receivable and Significant Concentrations (Details 1) - Unbilled receivables [Member]
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
U.S. Department of Homeland Security HQ [Member]    
As a % of receivables 11.00% 11.00%
U.S. Immigration and Customs Enforcement [Member]    
As a % of receivables 37.00% 27.00%
U.S. Coast Guard [Member]    
As a % of receivables 11.00% 0.00%
U.S. Transportation Safety Administration [Member]    
As a % of receivables 10.00% 12.00%