Segment Information - Schedule of Revenue by Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenue	$ 440,333	$ 174,451	$ 42,733
United States
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenue	343,625	134,920	32,301
Rest of the world
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenue	$ 96,708	$ 39,531	$ 10,432