Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2016	Oct. 31, 2015
Disclosure Basis Of Presentation Details [Line Items]
Decrease in net revenue	$ 121,118	$ 114,948
Increase to cost of sales	68,759	62,947
Increase to selling and marketing expenses	18,180	$ 15,233
Out-of-period adjustments
Disclosure Basis Of Presentation Details [Line Items]
Out of period adjustment	1,000
Decrease in net revenue	(400)
Increase to cost of sales	400
Increase to selling and marketing expenses	$ 200