Summary of status of options granted under stock option plans and changes in options outstanding (Detail) - USD ($)	12 Months Ended
	Oct. 31, 2016	Oct. 31, 2015
Shares
Aggregate intrinsic value of options exercised during year	$ 99,000
Stock Option
Shares
Options Outstanding at beginning of year	1,240,100	1,044,932
Options granted	104,936	396,039
Options exercised	(180,067)	(153,837)
Options forfeited	(157,118)	(47,034)
Options outstanding at end of year	1,007,851	1,240,100
Options exercisable at end of year	724,457	782,648
Options vested and expected to vest at end of year	1,002,522	1,233,543
Aggregate intrinsic value of options exercised during year	$ 456,000	$ 363,000
Option price lower range	$ 2.30	$ 0.05
Option price upper range	6.91	6.91
Weighted Average Exercise Price
Options outstanding at beginning of year	3.64	3.27
Options granted	3.36	4.21
Options exercised	0.27	2.12
Options forfeited	4.53	5.11
Options outstanding at end of year	4.07	3.64
Options exercisable at end of year	3.93	3.02
Options vested and expected to vest at end of year	$ 4.07	$ 3.63