Summary of Status of Options Granted under Stock Option Plans and Changes in Options Outstanding (Detail) - Jul. 31, 2015 - Stock Option - $ / shares	Total
Shares
Options Outstanding at beginning of year	1,044,932
Options granted	381,039
Options exercised	(12,004)
Options canceled or expired	(8,788)
Options outstanding at end of year	1,405,179
Options exercisable at end of year	800,319
Options vested and expected to vest at end of year	1,390,719
Weighted Average Exercise Price
Options outstanding at beginning of year	$ 3.26
Options granted	4.19
Options exercised	2.95
Options canceled or expired	4.49
Options outstanding at end of year	3.51
Options exercisable at end of year	2.56
Options vested and expected to vest at end of year	$ 3.50