CONCENTRATION OF CREDIT RISK AND SIGNIFICANT CUSTOMERS - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($) Customer	Sep. 30, 2015 Customer	Sep. 30, 2016 USD ($) Customer	Sep. 30, 2015 Customer	Mar. 31, 2016 USD ($) Customer
Concentration Risk [Line Items]
Related party prepaid expenses and other current assets | $	$ 42,444		$ 42,444		$ 78,399
Affiliated Entity
Concentration Risk [Line Items]
Related party prepaid expenses and other current assets | $	$ 17,513		$ 17,513		$ 44,161
Customer Concentration Risk | Indirect Customer | Accounts receivable
Concentration Risk [Line Items]
Number of customers contributing to more than 10%			0		0
Customer Concentration Risk | Indirect Customer | Sales Revenue
Concentration Risk [Line Items]
Number of customers contributing to more than 10%	0	0	0	0
Customer Concentration Risk | Direct Customer | Accounts receivable
Concentration Risk [Line Items]
Number of customers contributing to more than 10%			1		1
Customer Concentration Risk | Direct Customer | Sales Revenue
Concentration Risk [Line Items]
Number of customers contributing to more than 10%	1	1	1	1