Stock Incentive Plan - Summary of Stock Options Activity under Company's Equity Plans and Related Information (Detail) - Employee Stock Option [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares Underlying Outstanding Options, Beginning balance	4,275,451	4,008,725	3,262,518
Number of Shares Underlying Outstanding Options, Options granted	1,449,350	1,213,344	1,664,158
Number of Shares Underlying Outstanding Options, Options exercised	(625,496)	(465,385)	(545,370)
Number of Shares Underlying Outstanding Options, Options cancelled	(460,213)	(481,233)	(372,581)
Number of Shares Underlying Outstanding Options, Ending balance	4,639,092	4,275,451	4,008,725	3,262,518
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Options Outstanding, Weighted-Average Exercise Price, Beginning balance	$ 5.75	$ 2.51	$ 1.10
Options Outstanding, Weighted-Average Exercise Price, Options granted	9.50	14.39	4.79
Options Outstanding, Weighted-Average Exercise Price, Options exercised	1.86	2.07	0.84
Options Outstanding, Weighted-Average Exercise Price, Options cancelled	7.87	4.04	2.86
Options Outstanding, Weighted-Average Exercise Price, Ending balance	$ 7.24	$ 5.75	$ 2.51	$ 1.10
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	7 years 1 month 24 days	7 years 3 months 15 days	7 years 7 months 24 days	7 years 9 months 26 days
Options Outstanding, Aggregate Intrinsic Value	$ 24,146	$ 17,468	$ 31,716	$ 9,807
Number of Shares Underlying Outstanding Options, Exercisable at July 31, 2016	2,372,431
Number of Shares Underlying Outstanding Options, Vested and expected to vest July 31, 2016	4,207,727
Options Outstanding, Weighted-Average Exercise Price, Exercisable at July 31, 2016	$ 4.27
Options Outstanding, Weighted-Average Exercise Price, Vested and expected to vest at July 31, 2016	$ 6.93
Options Outstanding, Weighted-Average Remaining Contractual Life (Years), Exercisable at July 31, 2016	5 years 6 months 18 days
Options Outstanding, Weighted-Average Remaining Contractual Life (Years), Vested and expected to vest at July 31. 2016	7 years
Options Outstanding, Aggregate Intrinsic Value, Exercisable at July 31, 2016	$ 19,375
Options Outstanding, Aggregate Intrinsic Value, Vested and expected to vest at July 31, 2016	$ 23,169