Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jul. 31, 2017	Jul. 31, 2016
Operating activities:
Net loss	$ (55,903)	$ (43,354)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation, amortization and accretion	3,288	1,972
Stock-based compensation	20,884	7,033
Amortization of deferred commissions	8,333	6,389
Other	689	(114)
Changes in operating assets and liabilities:
Accounts receivable	(1,311)	690
Deferred commissions	(7,261)	(6,122)
Prepaid expenses and other assets	(5,940)	(3,403)
Accounts payable	1,183	1,650
Accrued compensation	2,562	(2,901)
Accrued expenses and other liabilities	(52)	(169)
Deferred revenue	17,604	11,456
Net cash used in operating activities	(15,924)	(26,873)
Investing activities:
Capitalization of internal-use software costs	(2,743)	(2,325)
Purchases of property and equipment and other	(5,156)	(3,029)
Purchases of securities available for sale	(86,776)	0
Proceeds from sales of securities available for sale	1,538	2,207
Proceeds from maturities and redemption of securities available for sale	12,835	5,000
Net cash provided by (used in) investing activities	(80,302)	1,853
Financing activities:
Proceeds from initial public offering, net of underwriters' discounts and commissions	199,948	0
Payments of deferred offering costs	(4,038)	(806)
Proceeds from stock option exercises, net of repurchases, and other	3,916	660
Principal payments on financing arrangements	(273)	(143)
Net cash provided by (used in) financing activities	199,553	(289)
Effects of changes in foreign currency exchange rates on cash and cash equivalents	134	(54)
Net increase (decrease) in cash, cash equivalents and restricted cash	103,461	(25,363)
Cash, cash equivalents and restricted cash at beginning of year	23,282	58,081
Cash, cash equivalents and restricted cash at end of year	126,743	32,718
Non-cash investing and financing activities:
Vesting of early exercised common stock options	693	707
Issuance of common stock in connection with warrant exercises	272	0
Deferred offering costs, accrued but not yet paid	0	207
Property and equipment and other, accrued but not yet paid	271	987
Issuance of common stock in connection with business combination	2,160	0
Conversion of redeemable convertible preferred stock to common stock	228,362	0
Reconciliation of cash, cash equivalents and restricted cash within the condensed consolidated balance sheets to the amounts shown in the statements of cash flows above:
Total cash, cash equivalents and restricted cash	$ 23,282	$ 58,081