CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jul. 31, 2020	Jul. 31, 2019
Cash flows from operating activities
Net loss	$ (118,492)	$ (70,576)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	5,722	6,029
Stock-based compensation	68,092	31,671
Amortization of debt discount and issuance costs	24,217	6,498
Amortization of finance right-of-use assets	1,988	1,988
Amortization of operating right-of-use assets	2,854	1,119
Non-cash interest on finance lease liabilities	0	1,823
Deferred income taxes	(148)	(4,232)
Accretion of discount on short-term investments	(221)	(2,751)
Change in operating assets and liabilities:
Accounts receivable	(2,408)	6,220
Prepaid expenses and other current assets	1,846	(125)
Deferred commissions	(8,993)	(7,046)
Other long-term assets	(156)	27
Accounts payable	(1,410)	440
Accrued liabilities	3,393	8,285
Operating lease liabilities	(38)	(1,082)
Deferred revenue	4,956	12,333
Other liabilities, non-current	2,890	0
Net cash used in operating activities	(15,908)	(9,379)
Cash flows from investing activities
Purchases of property and equipment	(5,296)	(1,596)
Acquisition, net of cash acquired	0	(38,629)
Proceeds from maturities of marketable securities	285,000	280,000
Purchases of marketable securities	(510,006)	(209,025)
Net cash provided by (used in) investing activities	(230,302)	30,750
Cash flows from financing activities
Payments of issuance costs for convertible senior notes	(4,154)	0
Proceeds from exercise of stock options, including early exercised stock options	7,051	11,350
Proceeds from the issuance of common stock under the Employee Stock Purchase Plan	8,963	6,394
Repurchase of early exercised stock options	(11)	(31)
Principal repayments of finance leases	(2,284)	0
Net cash provided by financing activities	9,565	17,713
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(47)	(233)
Net increase (decrease) in cash, cash equivalents and restricted cash	(236,692)	38,851
Cash, cash equivalents and restricted cash, beginning of period	706,706	148,347
Cash, cash equivalents and restricted cash, end of period	470,014	187,198
Cash paid during the period for:
Income taxes, net of refunds	658	1,523
Interest expense	3,535	1,125
Reconciliation of cash, cash equivalents and restricted cash within the condensed consolidated balance sheets, end of period, to the amounts shown in the statements of cash flows above
Total cash, cash equivalents and restricted cash	$ 470,014	$ 187,198