Summary of status of options granted under stock option plans and changes in options outstanding (Detail)	6 Months Ended
	Apr. 30, 2016 $ / shares shares
Shares
Options Outstanding at beginning of year | shares	1,240,100
Options granted | shares	84,936
Options exercised | shares	(180,067)
Options canceled or expired | shares	(37,320)
Options outstanding at end of year | shares	1,107,649
Options exercisable at end of year | shares	620,469
Options vested and expected to vest at end of year | shares	1,101,580
Weighted Average Exercise Price
Options outstanding at beginning of year | $ / shares	$ 3.64
Options granted | $ / shares	3.58
Options exercised | $ / shares	0.27
Options canceled or expired | $ / shares	4.29
Options outstanding at end of year | $ / shares	4.17
Options exercisable at end of year | $ / shares	3.89
Options vested and expected to vest at end of year | $ / shares	$ 4.16