Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	[3]
Cash flows from operating activities:
Net loss	$ (25,962)	$ (27,706)	[1],[2]
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Stock-based compensation	14,135	8,906
Depreciation, amortization and accretion	2,069	1,575
Amortization of debt discount and issuance costs	2,571	0
Amortization of deferred commissions	4,572	2,162
Deferred income taxes	(348)	0
Other	161	270
Changes in operating assets and liabilities:
Accounts receivable	1,719	2,243
Deferred commissions	(5,693)	(3,033)
Prepaid expenses and other assets	(3,983)	(3,756)
Accounts payable	2,339	3,236
Accrued compensation	329	(2,121)
Accrued expenses and other liabilities	(1,051)	323
Deferred revenue	13,114	8,215
Net cash provided by (used in) operating activities	3,972	(9,686)
Cash flows from investing activities:
Capitalization of internal-use software costs	(1,051)	(1,208)
Purchases of property and equipment	(4,477)	(2,448)
Purchases of securities available for sale	(252,914)	0
Proceeds from maturities of securities available for sale	19,500	10,335
Proceeds from sales of securities available for sale	0	1,538
Net cash provided by (used in) investing activities	(238,942)	8,217
Cash flows from financing activities:
Proceeds from initial public offering, net of underwriters' discounts and commissions	0	199,997
Proceeds from issuance of convertible senior notes, net of issuance costs	335,055	0
Purchase of convertible senior notes hedge	(80,040)	0
Proceeds from issuance of warrants related to convertible notes	52,440	0
Payments of deferred offering costs	0	(2,246)
Proceeds from stock option exercises, net of repurchases	12,196	2,564
Other	(206)	(207)
Net cash provided by financing activities	319,445	200,108
Effects of changes in foreign currency exchange rates on cash and cash equivalents	(387)	68
Net increase in cash, cash equivalents and restricted cash	84,088	198,707
Cash, cash equivalents and restricted cash at beginning of period	136,233	23,282
Cash, cash equivalents and restricted cash at end of period	220,321	221,989
Non-cash investing and financing activities:
Vesting of early exercised common stock options	243	328
Issuance of common stock in connection with warrant exercises	0	272
Deferred offering costs accrued but not yet paid	63	1,772
Property and equipment acquired through tenant improvement allowance	3,329	0
Property and equipment and other accrued but not yet paid	147	1,931
Issuance of common stock in connection with business combination	0	2,160
Conversion of redeemable convertible preferred stock to common stock	0	228,362
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	$ 136,233	$ 23,282

[1] See Note 2 for a summary of adjustments.

[2] See Note 2 for a summary of adjustments.

[3] See Note 2 for a summary of adjustments.