LEASES - Operating Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Leases [Abstract]
Lease cost under long-term operating leases	$ 3,276	$ 6,521
Lease cost under short-term operating leases	897	1,749
Variable lease cost under short-term and long-term operating leases	1,063	2,275
Total operating lease cost	$ 5,236	$ 10,545