EARNINGS (LOSS) PER SHARE - Reconciliation of Earnings (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Debt Instrument [Line Items]
Net income (loss)	$ (9,627)	$ (10,333)	$ (28,745)	$ 44,248
Less: Preferred dividends on redeemable preferred stock	(525)	(529)	(1,598)	(799)
Net income (loss) attributable to common stockholders	(10,152)	(10,862)	(30,343)	43,449
Effect of dilutive securities:
Net income (loss) attributable to common stockholders after assumed conversions	$ (10,152)	$ (10,862)	$ (30,343)	$ 49,485
Weighted average common shares outstanding (in shares)	61,393	60,076	61,111	58,281
Weighted average common equivalent shares arising from dilutive stock options, restricted stock, convertible notes and convertible preferred stock (in shares)	0	0	0	20,653
Weighted average number of common and potential common shares (in shares)	61,393	60,076	61,111	78,934
Basic net earnings (loss) per share attributable to common stockholders (usd per share)	$ (0.17)	$ (0.18)	$ (0.50)	$ 0.75
Diluted net earnings (loss) per share attributable to common stockholders (usd per share)	$ (0.17)	$ (0.18)	$ (0.50)	$ 0.63
5.25% Convertible Senior Notes Due 2019
Effect of dilutive securities:
Dilutive securities	$ 0	$ 0	$ 0	$ 5,248
Contingent Redeemable Preferred Stock
Effect of dilutive securities:
Dilutive securities	$ 0	$ 0	$ 0	$ 788