DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Summary of Effect of Foreign Exchange Forward Contracts on Other Comprehensive Income and Results of Operations (Details) - Forward contracts - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Loss Recognized in OCI on Derivative	$ (73)
Loss Recognized in OCI on Derivative		$ (519)
Gain (Loss) Reclassified from Accumulated OCI into Income	46
Research and development
Derivative Instruments, Gain (Loss) [Line Items]
Loss Recognized in OCI on Derivative	(73)
Loss Recognized in OCI on Derivative		(519)
Gain (Loss) Reclassified from Accumulated OCI into Income	(5)
Sales and marketing
Derivative Instruments, Gain (Loss) [Line Items]
Loss Recognized in OCI on Derivative
Loss Recognized in OCI on Derivative
Gain (Loss) Reclassified from Accumulated OCI into Income	$ 51
Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income		94
Cash flow hedges | Research and development
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income		30
Cash flow hedges | Sales and marketing
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income		$ 64