Capital Stock - Schedule of Ordinary Shares Reserved for Future Issuance (Detail)	Oct. 31, 2013	Jan. 31, 2013
Options and restricted stock units [Member]
Class of Stock [Line Items]
Shares reserved	6,235,400	5,818,126
Employee stock purchase plan [Member]
Class of Stock [Line Items]
Shares reserved	456,410	460,445
Warrants [Member]
Class of Stock [Line Items]
Shares reserved		36,292