Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Oct. 31, 2015	Oct. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (169,458)	$ (135,596)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	23,118	9,751
Stock-based compensation expense	36,198	17,241
Contribution of common stock to the Pure Good Foundation	11,900	0
Other	0	3
Changes in operating assets and liabilities:
Accounts receivable, net	(53,094)	(30,735)
Inventory	(3,420)	(13,072)
Deferred commissions	(8,472)	(4,063)
Prepaid expenses and other assets	(2,065)	(2,368)
Accounts payable	10,224	4,575
Accrued compensation and other liabilities	17,216	7,670
Deferred revenue	87,987	36,918
Net cash used in operating activities	(49,866)	(109,676)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of property and equipment	(29,495)	(30,902)
Purchases of intangible assets	0	(9,125)
Increase in restricted cash	(2,484)	(1,613)
Net cash used in investing activities	(31,979)	(41,640)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from initial public offering, net of issuance costs	459,425	0
Proceeds from issuance of convertible preferred stock, net of issuance costs	0	280,820
Net proceeds from exercise of stock options, including proceeds from repayment of promissory notes	4,710	7,167
Repurchase of common stock in connection with a tender offer	0	(30,120)
Payments of deferred offering costs	(1,690)	0
Net cash provided by financing activities	462,445	257,867
Net increase in cash and cash equivalents	380,600	106,551
Cash and cash equivalents, beginning of period	192,707	130,885
Cash and cash equivalents, end of period	573,307	237,436
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Cash paid for income taxes	820	332
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING INFORMATION
Conversion of convertible preferred stock to common stock upon initial public offering	543,940	0
Purchase of property and equipment	1,750	1,462
Vesting of early exercised stock options and restricted stock awards	1,543	732
Cashless exercise of stock options during a tender offer	0	2,057
Unpaid deferred offering costs	$ 2,748	$ 0