Summary of status of options granted under stock option plans and changes in options outstanding (Detail) - USD ($)	12 Months Ended
Oct. 31, 2018	Oct. 31, 2017
Shares
Options exercisable at end of year	675,033	926,272
Option price lower range	$ 1.90	$ 1.07
Option price upper range	5.88	6.91
Weighted Average Exercise Price
Options canceled or expired	$ 4.98	$ 4.10
Stock Option
Shares
Options outstanding at beginning of year	1,159,771	1,007,851
Options granted	269,635	449,068
Options exercised	(418,955)	(36,763)
Options canceled or expired	(68,085)	(260,385)
Options outstanding at end of year	942,366	1,159,771
Options vested and expected to vest at end of year	940,144	1,159,002
Aggregate intrinsic value of options exercised during year	$ 1,207,148	$ 55,000
Weighted Average Exercise Price
Options outstanding at beginning of year	$ 3.19	$ 4.07
Options granted	2.44	1.61
Options exercised	2.66	1.50
Options outstanding at end of year	3.09	3.19
Options exercisable at end of year	3.01	3.08
Options vested and expected to vest at end of year	$ 3.09	$ 3.19

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.