Stock-based compensation and equity transactions - Additional Information (Detail) - USD ($)	3 Months Ended
	Jan. 31, 2016	Jan. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining life of options outstanding	5 years 14 days
Weighted average remaining contractual life of options exercisable	3 years 5 months 12 days	3 years
Weighted average life of options vested and expected to vest	5 years 11 days	5 years
Aggregate intrinsic value of options outstanding	$ 1,200,000
Aggregate intrinsic value of options exercisable	1,200,000
Aggregate intrinsic value of options vested and expected to vest	1,200,000
Non-vested stock-based arrangements yet to be recognized	$ 654,000
Stock based arrangements yet to be recognized, weighted average period expected to be recognized	5 years 7 months 24 days
Stock Issued During Period, Value, Stock Options Exercised		$ 1,060,000
Non-employee director annual grant	$ 30,000
Options granted for each non-employee director	51,192
Value of stock option issued	$ 15,000
Fair value of stock option	$ 0.87
Stock based compensation expense	$ 52,000	$ 50,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 1.00
Proceeds from Issuance of Common Stock		$ 252,381
Employee | Incentive stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, grants in period, gross		127,558
Cost of Sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	10,000	$ 15,000
Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 42,000	$ 35,000