Consolidated Balance Sheets (Parenthetical) - $ / shares	Jan. 31, 2016	Jan. 31, 2015
Statement Of Financial Position [Abstract]
Preference shares, par value	$ 0.00045	$ 0.00045
Preference shares, shares authorized	20,000,000	20,000,000
Preference shares, shares issued	0	0
Preference shares, shares outstanding	0	0
Ordinary shares, par value	$ 0.00045	$ 0.00045
Ordinary shares, shares authorized	200,000,000	200,000,000
Ordinary shares, shares issued	32,333,359	30,837,529
Ordinary shares, shares outstanding	32,333,359	30,837,529