Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Revenue:
Product	$ 590,001	$ 375,733	$ 154,836
Support	137,976	64,600	19,615
Total revenue	727,977	440,333	174,451
Cost of revenue:
Product	194,150	132,870	63,425
Support	58,129	35,023	14,127
Total cost of revenue	252,279	167,893	77,552
Gross profit	475,698	272,440	96,899
Operating expenses:
Research and development	245,817	166,645	92,707
Sales and marketing	360,035	240,574	152,320
General and administrative	84,652	75,402	32,354
Legal settlement	30,000	0	0
Total operating expenses	720,504	482,621	277,381
Loss from operations	(244,806)	(210,181)	(180,482)
Other income (expense), net	1,627	(2,002)	(1,412)
Loss before provision for income taxes	(243,179)	(212,183)	(181,894)
Provision for income taxes	1,887	1,569	1,337
Net loss	$ (245,066)	$ (213,752)	$ (183,231)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (1.26)	$ (2.59)	$ (6.56)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted (in shares)	194,714	82,460	27,925