Summary of status of options granted under stock option plans and changes in options outstanding (Detail) - USD ($)	12 Months Ended
	Oct. 31, 2015	Oct. 31, 2014
Shares
Aggregate intrinsic value of options exercised during year	$ 1,500,000
Option price lower range	$ 0.05	$ 0.05
Option price upper range	$ 6.91	$ 6.91
Stock Option
Shares
Options Outstanding at beginning of year	1,044,932	988,215
Options granted	396,039	328,903
Options exercised	(153,837)	(204,683)
Options forfeited	(47,034)	(67,503)
Options outstanding at end of year	1,240,100	1,044,932
Options exercisable at end of year	782,648	748,843
Options vested and expected to vest at end of year	1,233,543	1,040,541
Aggregate intrinsic value of options exercised during year	$ 363,000	$ 1,103,000
Weighted Average Exercise Price
Options outstanding at beginning of year	$ 3.27	$ 2.24
Options granted	4.21	5.83
Options exercised	2.12	2.80
Options forfeited	5.11	2.10
Options outstanding at end of year	3.27	3.27
Options exercisable at end of year	3.02	2.38
Options vested and expected to vest at end of year	$ 3.63	$ 3.25