REVENUE RECOGNITION - Impact of the Adoption on Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Apr. 30, 2019	Jan. 31, 2019	Aug. 01, 2018	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018	Jul. 31, 2017
ASSETS
Inventories, net	$ 25,404		$ 26,553	$ 47,786
Prepaid expenses and other current assets	33,399		37,456	13,415
Total current assets	202,441		267,089	264,281
Total assets	734,750		829,858	827,050
Liabilities
Other current liabilities	43,753		38,699	42,029
Total current liabilities	220,499		273,026	276,356
Total liabilities	607,166		680,900	684,230
Stockholders' equity
Accumulated deficit	(7,387,774)		(7,357,431)	(7,363,569)
Total stockholders’ equity	92,386	$ 94,537	113,766	107,628	$ 118,658	$ 128,697	$ 62,971
Total liabilities, contingently redeemable preferred stock and stockholders’ equity	734,750		829,858	827,050
Calculated under Revenue Guidance in Effect before Topic 606
ASSETS
Inventories, net	47,950			47,786
Prepaid expenses and other current assets	10,975			13,415
Total current assets	202,563			264,281
Total assets	734,872			827,050
Liabilities
Other current liabilities	50,811			42,029
Total current liabilities	227,557			276,356
Total liabilities	614,224			684,230
Stockholders' equity
Accumulated deficit	(7,394,710)			(7,363,569)
Total stockholders’ equity	85,450			107,628
Total liabilities, contingently redeemable preferred stock and stockholders’ equity	734,872			$ 827,050
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606
ASSETS
Inventories, net	(22,546)		(21,233)
Prepaid expenses and other current assets	22,424		24,041
Total current assets	(122)		2,808
Total assets	(122)		2,808
Liabilities
Other current liabilities	(7,058)		(3,330)
Total current liabilities	(7,058)		(3,330)
Total liabilities	(7,058)		(3,330)
Stockholders' equity
Accumulated deficit	6,936		6,138
Total stockholders’ equity	6,936		6,138
Total liabilities, contingently redeemable preferred stock and stockholders’ equity	$ (122)		$ 2,808