FAIR VALUE MEASUREMENTS - Schedule of Reconciliation of Changes in Fair Value of Level III Financial Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Payment received	$ (5,133)	$ 0
Fair value, measurements, recurring | Contingent Purchase Consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	(7,293)
Increase in fair value and accretion expense (included within research and development expense)	(38)
Payments made	2,657
Balance at end of period	(4,674)
Fair value, measurements, recurring | Contingently Returnable Consideration
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	16,131
Payment received	(7,790)
Balance at end of period	$ 8,341