SUPPLEMENTARY FINANCIAL INFORMATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Valuation allowance for deferred income taxes
Movement in valuation and qualifying accounts
Beginning Balance	$ 170,574	$ 133,468	$ 40,774
Additions	13,511	37,106	92,694
Deductions	0	0	0
Other	0	0	0
Ending Balance	184,085	170,574	133,468
Price protection, sales returns and other allowances
Movement in valuation and qualifying accounts
Beginning Balance	45,153	69,305	74,078
Additions	127,744	64,498	50,114
Deductions	(100,934)	(86,622)	(57,982)
Other	(6,849)	(2,028)	3,095
Ending Balance	65,114	45,153	69,305
Price protection
Movement in valuation and qualifying accounts
Additions	65,336	36,546	16,669
Other sales allowances
Movement in valuation and qualifying accounts
Additions	45,850	23,073	24,402
Returns
Movement in valuation and qualifying accounts
Additions	16,558	4,879	9,043
Allowance for doubtful accounts
Movement in valuation and qualifying accounts
Beginning Balance	399	1,166	1,440
Additions	974	0	0
Deductions	(4)	(767)	(274)
Other	0	0	0
Ending Balance	1,369	399	1,166
Total accounts receivable allowances
Movement in valuation and qualifying accounts
Beginning Balance	45,552	70,471	75,518
Additions	128,718	64,498	50,114
Deductions	(100,938)	(87,389)	(58,256)
Other	(6,849)	(2,028)	3,095
Ending Balance	$ 66,483	$ 45,552	$ 70,471