Stock-based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified			9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	1 Months Ended
	Oct. 31, 2013	Aug. 27, 2013	Oct. 31, 2013 Restricted stock units [Member]	Jan. 31, 2013 Restricted stock units [Member]	Oct. 31, 2013 Employee stock option [Member]	Jan. 31, 2013 Employee stock option [Member]	Aug. 27, 2013 Service condition restricted stock units [Member]	Aug. 27, 2013 Service and performance conditioned restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost, stock options					$ 5.9	$ 7.3
Total unrecognized compensation cost, restricted stock units			18.2	2.4
Weighted-average period			3 years 2 months 16 days	1 year 9 months 7 days	1 year 11 months 16 days	2 years 3 months 4 days
Closing price of ordinary shares	$ 20.55
Ordinary shares granted as awards of restricted stock units			1,240,472				1,058,860	154,500
Fair value on grant date per ordinary share		$ 14.56
Vesting period of RSUs							1/16th of the RSUs shall vest each 3 months following the vesting commencement date, so as to be 100% vested on the fourth anniversary of the vesting commencement date	1/8th of the RSUs shall vest each 3 months following the vesting commencement date, so as to be 100% vested on the second anniversary of the vesting commencement date
Aggregate intrinsic value of unvested restricted stock units			$ 30.5