Quarterly report pursuant to Section 13 or 15(d)

REVENUE -Remaining Performance Obligations (Details)

v3.19.1
REVENUE -Remaining Performance Obligations (Details)
$ in Thousands
Mar. 31, 2019
USD ($)
Transaction price allocated to the remaining performance obligations  
Remaining performance obligation $ 478,675
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01  
Transaction price allocated to the remaining performance obligations  
Remaining performance obligation $ 138,044
Expected timing of satisfaction 9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01  
Transaction price allocated to the remaining performance obligations  
Remaining performance obligation $ 136,482
Expected timing of satisfaction 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01  
Transaction price allocated to the remaining performance obligations  
Remaining performance obligation $ 95,662
Expected timing of satisfaction 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01  
Transaction price allocated to the remaining performance obligations  
Remaining performance obligation $ 108,487
Expected timing of satisfaction