Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2015	Oct. 31, 2014	Oct. 31, 2015	Oct. 31, 2014	Jan. 31, 2015
Accounting Policies [Abstract]
Restricted cash	$ 7,100		$ 7,100		$ 4,600
Deferred commissions, current	13,612		13,612		9,431
Deferred income taxes, non-current	11,800		11,800		$ 7,500
Sales commission expenses	$ 16,500	$ 11,700	$ 38,600	$ 21,800