Summary of Significant Accounting Policies - Summary of Customers that Accounted for at Least 10% of Total Current and Non-Current Trade Receivables (Details) (Credit Concentration Risk, Accounts Receivable)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Concentration Risk, Percentage 41.70% 41.70%
Fluor    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Concentration Risk, Percentage 14.40% 19.40%
Alion Science and Technology Corporation    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Concentration Risk, Percentage 11.80% 0.00%
Army Contracting Command – Rock Island    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Concentration Risk, Percentage 4.70% 13.80%
Hellenic Fire Brigade    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Concentration Risk, Percentage 10.80% [1] 8.50% [1]
[1] On May 23, 2012, the Company entered into a three year agreement with the NATO Maintenance and Supply Agency (“NAMSA”), pursuant to which the Company agreed to supply aerial firefighting services in Greece for the 2012 to 2014 firefighting seasons. Prior to the agreement with NAMSA, the Company contracted directly with the Hellenic Fire Brigade to provide firefighting services in Greece. At December 31, 2013, the receivable from Hellenic Fire Brigade was classified in other non-current assets due to the long-term nature of obtaining resolution regarding the Company’s permanent establishment status in Greece.