Reportable Segment Information (Parenthetical) (Detail) - USD ($) $ in Thousands	Apr. 30, 2016	Jul. 31, 2015	Apr. 30, 2015	Jul. 31, 2014
Segment Reporting Information [Line Items]
Cash and cash equivalents	$ 128,124	$ 123,800	$ 119,835	$ 114,540
Corporate
Segment Reporting Information [Line Items]
Cash and cash equivalents	$ 92,000	$ 86,200