BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - CONCENTRATION RISK (Details)	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Net revenue | Customer concentration risk | Five largest customers
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	65.50%	58.90%	64.60%
Net revenue | Customer concentration risk | One customer
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	26.30%	20.70%	13.30%
Net revenue | Customer concentration risk | Additional customer one
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	14.20%	15.50%	11.70%
Net revenue | Customer concentration risk | Additional customer two
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	10.90%		21.00%
Net revenue | Customer concentration risk | Additional customer three
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate			10.40%
Gross accounts receivable | Credit concentration risk | Five largest customers
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	69.90%	73.90%
Gross accounts receivable | Credit concentration risk | One customer
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	40.20%	35.20%
Gross accounts receivable | Credit concentration risk | Additional customer one
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	17.40%	16.80%
Gross accounts receivable | Credit concentration risk | Additional customer two
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate		12.10%
Gross accounts receivable | Credit concentration risk | Customers individually accounting for more than 10%
Concentration of Credit Risk and Accounts Receivable
Concentration risk rate	57.60%	64.10%