Issue of options under equity incentive plan - Schedule of stock option activity (Detail) (2010 Equity Incentive Plan [Member], USD $)	9 Months Ended	12 Months Ended
	Jul. 31, 2012	Oct. 31, 2011
Options Granted May 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, outstanding at beginning of period	750,000	0
Number of options, granted	0	750,000
Number of options, outstanding at end of period	750,000	750,000
Weighted average exercise price, outstanding beginning of period	$ 1.00	$ 0
Weighted average exercise price, granted		$ 1.00
Weighted average exercise price, outstanding end of period	$ 1.00	$ 1.00
Options Granted December 13, 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, outstanding at beginning of period	2,500,000	0
Number of options, granted	0	2,500,000
Number of options, outstanding at end of period	2,500,000	2,500,000
Weighted average exercise price, outstanding beginning of period	$ 1.00	$ 0
Weighted average exercise price, granted		$ 1.00
Weighted average exercise price, outstanding end of period	$ 1.00	$ 1.00