Annual report pursuant to Section 13 and 15(d)

Business Segments and Customer Information, Major Customers (Details)

v3.6.0.2
Business Segments and Customer Information, Major Customers (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 691,790 $ 533,982 $ 424,071
Percentage of revenue by customer 100.00% 100.00% 100.00%
U. S. Postal Service      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 181,215 $ 184,876 $ 167,268
Percentage of revenue by customer 26.20% 34.60% 39.40%
U.S. Navy      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 190,155 $ 98,887 $ 88,007
Percentage of revenue by customer 27.50% 18.50% 20.70%
U.S. Army      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 139,764 $ 80,086 $ 101,714
Percentage of revenue by customer 20.20% 15.00% 24.00%
U.S. Air Force      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 3,482 $ 3,558 $ 3,323
Percentage of revenue by customer 0.50% 0.70% 0.80%
Total - DoD      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 333,401 $ 182,531 $ 193,044
Percentage of revenue by customer 48.20% 34.20% 45.50%
Commercial Aviation      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 131,067 $ 119,729 $ 0
Percentage of revenue by customer 19.00% 22.40% 0.00%
Other Commercial      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 10,721 $ 4,653 $ 3,680
Percentage of revenue by customer 1.50% 0.90% 0.90%
Total - Commercial      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 141,788 $ 124,382 $ 3,680
Percentage of revenue by customer 20.50% 23.30% 0.90%
Department of Energy      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 11,708 $ 16,020 $ 19,000
Percentage of revenue by customer 1.70% 3.00% 4.50%
Social Security Administration      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 9,762 $ 9,666 $ 10,153
Percentage of revenue by customer 1.40% 1.80% 2.40%
Other Government      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 13,916 $ 16,507 $ 30,926
Percentage of revenue by customer 2.00% 3.10% 7.30%
Total - Other Civilian Agencies      
Revenue, Major Customer [Line Items]      
Revenue, by customer $ 35,386 $ 42,193 $ 60,079
Percentage of revenue by customer 5.10% 7.90% 14.20%