Quarterly report pursuant to Section 13 or 15(d)

Business Segments and Customer Information, Major Customers (Details)

v3.5.0.2
Business Segments and Customer Information, Major Customers (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Revenue, Major Customer [Line Items]        
Revenue $ 160,473 $ 131,126 $ 304,109 $ 251,917
Percentage of revenue by customer 100.00% 100.00% 100.00% 100.00%
U.S. Postal Service [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 44,295 $ 45,339 $ 90,592 $ 89,519
Percentage of revenue by customer 27.60% 34.50% 29.80% 35.50%
U.S. Navy [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 36,569 $ 22,607 $ 66,460 $ 44,004
Percentage of revenue by customer 22.80% 17.20% 21.90% 17.40%
U.S. Army [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 34,291 $ 18,557 $ 56,501 $ 37,728
Percentage of revenue by customer 21.40% 14.20% 18.50% 15.00%
U.S. Air Force [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 876 $ 924 $ 1,857 $ 1,714
Percentage of revenue by customer 0.50% 0.70% 0.60% 0.70%
Total Department of Defense [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 71,736 $ 42,088 $ 124,818 $ 83,446
Percentage of revenue by customer 44.70% 32.10% 41.00% 33.10%
Commercial Aviation [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 32,064 $ 31,904 $ 65,610 $ 54,668
Percentage of revenue by customer 20.00% 24.30% 21.60% 21.70%
Other Commercial [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 2,804 $ 1,760 $ 5,087 $ 2,967
Percentage of revenue by customer 1.70% 1.40% 1.70% 1.20%
Total - Commercial [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 34,868 $ 33,664 $ 70,697 $ 57,635
Percentage of revenue by customer 21.70% 25.70% 23.30% 22.90%
Department of Energy [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 3,006 $ 4,662 $ 5,909 $ 9,106
Percentage of revenue by customer 1.90% 3.60% 1.90% 3.60%
Social Security Administration [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 2,463 $ 2,271 $ 5,050 $ 4,721
Percentage of revenue by customer 1.50% 1.70% 1.70% 1.90%
Other Government [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 4,105 $ 3,102 $ 7,043 $ 7,490
Percentage of revenue by customer 2.60% 2.40% 2.30% 3.00%
Total - Other Civilian Agencies [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 9,574 $ 10,035 $ 18,002 $ 21,317
Percentage of revenue by customer 6.00% 7.70% 5.90% 8.50%