Earnings Per Share - Computations for Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Oct. 31, 2015	Oct. 31, 2014
Earnings (loss) per share:
Net income	$ 7,779	$ 7,694
Less: income allocated to participating securities	(55)	(83)
Income attributable to common shareholders — basic	7,724	7,611
Add: undistributed income attributable to participating securities	55	83
Less: undistributed income reallocated to participating securities	(54)	(82)
Income attributable to common shareholders — diluted	$ 7,725	$ 7,612
Weighted average shares outstanding — basic	31,279	31,042
Dilutive shares — stock options, RSUs and PSUs	591	426
Weighted average shares outstanding — diluted	31,870	31,468
Basic (in dollars per share)	$ 0.25	$ 0.25
Diluted (in dollars per share)	$ 0.24	$ 0.24