Goodwill and Intangible Assets - Summary of Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014
Goodwill [Roll Forward]
Balance at beginning of period	$ 14,744	$ 14,744	$ 0
Acquisition	0	0	14,744
Balance at end of period	$ 14,744	$ 14,744	$ 14,744