Capital Stock - Additional Information (Detail) - $ / shares	Feb. 01, 2015	Oct. 31, 2015	Jan. 31, 2015
Class Of Stock [Line Items]
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
Ordinary shares, shares authorized		200,000,000	200,000,000
2012 Equity Incentive Plan [Member]
Class Of Stock [Line Items]
Additional ordinary shares reserved for issuance	1,387,689
2012 Equity Incentive Plan [Member] | Scenario, plan automatically increased by the lessor of [Member]
Class Of Stock [Line Items]
Annual increase in ordinary shares for available for future issuance	3,500,000
Annual shares increase for future issuance by percentage under 2012 equity incentive plan	4.50%
2012 Employee Stock Purchase Plan [Member]
Class Of Stock [Line Items]
Additional ordinary shares reserved for issuance	385,469
2012 Employee Stock Purchase Plan [Member] | Scenario, plan automatically increased by the lessor of [Member]
Class Of Stock [Line Items]
Annual increase in ordinary shares for available for future issuance	1,500,000
Annual shares increase for future issuance by percentage under 2012 employee stock purchase plan	1.25%