Quarterly report pursuant to Section 13 or 15(d)

REVENUE RECOGNITION - Schedule of Revenue from third party customers (Details)

v3.20.2
REVENUE RECOGNITION - Schedule of Revenue from third party customers (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Disaggregation of Revenue [Line Items]        
Operating revenue from non-affiliates $ 282,507 $ 291,348 $ 529,056 $ 595,478
Operating revenue from affiliates 13,215 13,336 28,174 25,782
Reimbursable revenue from non-affiliates 8,918 13,536 17,603 30,136
Revenue 304,640 318,220 574,833 651,396
Revenue        
Disaggregation of Revenue [Line Items]        
Operating revenue from non-affiliates 282,060 290,939 528,189 594,672
Operating revenue from affiliates 3,267 5,365 7,861 9,840
Reimbursable revenue from non-affiliates 8,918 13,536 17,603 30,136
Revenue 294,245 309,840 553,653 634,648
Revenue not from contract with customer        
Disaggregation of Revenue [Line Items]        
Operating revenue from non-affiliates 447 409 867 806
Operating revenue from affiliates $ 9,948 $ 7,971 $ 20,313 $ 15,942