Stock-based compensation and equity transactions - Additional Information (Detail) (USD $)	3 Months Ended
	Jan. 31, 2014	Jan. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining life of options outstanding	4 years 9 months 29 days
Weighted average remaining contractual life of options exercisable	4 years 10 months 28 days
Weighted average life of options vested and expected to vest	4 years 9 months 29 days
Aggregate intrinsic value of options outstanding	$ 3,900,000
Aggregate intrinsic value of options exercisable	3,200,000
Aggregate intrinsic value of options vested and expected to vest	3,200,000
Non-vested stock-based arrangements yet to be recognized	380,000
Stock based arrangements yet to be recognized, weighted average period expected to be recognized	2 years 11 months 16 days
Weighted average fair value of stock options under Black-Scholes pricing model	$ 1.89	$ 1.01
Proceeds from exercise of stock options	341,000	1,314,000
Non-employee director annual grant	30,000
Options granted for each non-employee director	7,860
Value of stock option issued	15,000
Fair value of stock option	$ 1.91
Stock based compensation expense	47,000	33,000
Incentive stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive stock options	99,323
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock for exercise of stock option	109,763
Cost of Sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	9,000	9,000
Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 38,000	$ 24,000