Issue of options under equity incentive plan - Schedule of stock option activity (Detail) (2010 Equity Incentive Plan [Member], USD $)	24 Months Ended
	Oct. 31, 2012	Jan. 31, 2013
Options Granted December 13, 2010 [Member]
Number of options, granted	2,500,000
Number of options, outstanding at end of period	2,500,000	2,500,000
Weighted average exercise price, granted	$ 1.00
Weighted average exercise price, outstanding end of period	$ 1.00	$ 1
Options Granted May 2011 [Member]
Number of options, granted	750,000
Number of options, outstanding at end of period	750,000	750,000
Weighted average exercise price, granted	$ 1.00
Weighted average exercise price, outstanding end of period	$ 1.00	$ 1