Income Taxes - Schedule of Reconciliation Between the Provision (Benefit) for Income Taxes at the Statutory Rate and the Effective Tax Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Income Tax Disclosure [Abstract]
Provision at U.S. notional statutory rate	$ 20,700	$ 28,971	$ 17,692
U.S. state taxes	(216)	541	90
Non-U.S. foreign tax differential	(18,357)	(26,253)	(15,644)
Stock-based compensation	1,605	2,896	1,601
U.S. R&D credit	(2,226)	(3,517)	(2,298)
Valuation allowance	1,901	6,090	0
Other	(336)	(27)	24
Provision for income taxes	$ 3,071	$ 8,701	$ 1,465