Quarterly report pursuant to Section 13 or 15(d)

REVENUE - Disaggregation of revenue (Details)

v3.21.1
REVENUE - Disaggregation of revenue (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Disaggregation of revenue    
Revenue $ 60,851 $ 66,147
United States    
Disaggregation of revenue    
Revenue 51,190 57,647
Canada    
Disaggregation of revenue    
Revenue 9,661 8,500
Cost-plus reimbursement contracts    
Disaggregation of revenue    
Revenue 55,593 60,296
Fixed-price contracts    
Disaggregation of revenue    
Revenue $ 5,258 $ 5,851