Capital Stock - Additional Information (Detail) (USD $)	3 Months Ended
	Apr. 30, 2013	Jan. 31, 2013
Equity [Abstract]
Preference shares, shares authorized	20,000,000	20,000,000
Preference shares, par value	$ 0.00045	$ 0.00045
Preference shares, shares issued	0	0
Preference shares, shares outstanding	0	0
Company issued warrants to purchase Series B redeemable convertible preference shares, exercise price	3.582	3.582
Company issued warrants to purchase Series B redeemable convertible preference shares		36,292
Total ordinary share warrants exercised	25,125
Total ordinary share warrants outstanding	11,167	36,292
Total ordinary shares authorized	200,000,000	200,000,000