Quarterly report pursuant to Section 13 or 15(d)

REVENUE - Disaggregation of revenue (Details)

v3.10.0.1
REVENUE - Disaggregation of revenue (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2018
Disaggregation of revenue    
Revenue $ 47,975 $ 91,096
Cost-plus reimbursement contracts    
Disaggregation of revenue    
Revenue 39,332 73,109
Fixed-price contracts    
Disaggregation of revenue    
Revenue $ 8,643 $ 17,987