Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Jan. 31, 2018	Mar. 07, 2018	Jul. 31, 2017
Entity Information [Line Items]
Document Type	10-K
Document Period End Date	Jan. 31, 2018
Amendment Flag	false
Entity Registrant Name	Okta, Inc.
Entity Central Index Key	0001660134
Current Fiscal Year End Date	--01-31
Entity Filer Category	Non-accelerated Filer
Document Fiscal Year Focus	2018
Document Period Focus	FY
Entity Well-Known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 371.7
Class A Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		73,880,045
Class B Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		30,776,974

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Current assets:
Cash and cash equivalents	$ 127,949	$ 23,282
Short-term investments	101,765	14,390
Accounts receivable, net of allowances of $1,472 and $1,306	52,248	34,544
Deferred commissions	16,481	13,549
Prepaid expenses and other current assets	16,973	7,025
Total current assets	315,416	92,790
Property and equipment, net	12,540	11,026
Deferred commissions, noncurrent	10,971	10,050
Intangible assets, net	11,761	9,155
Goodwill	6,282	2,630
Other assets	10,427	4,984
Total assets	367,397	130,635
Current liabilities:
Accounts payable	9,566	9,387
Accrued expenses and other current liabilities	6,187	8,363
Accrued compensation	12,374	8,734
Deferred revenue	162,633	108,012
Total current liabilities	190,760	134,496
Deferred revenue, noncurrent	6,034	5,711
Other liabilities, noncurrent	7,017	6,079
Total liabilities	203,811	146,286
Commitments and contingencies (Note 9)
Redeemable convertible preferred stock, par value $0.0001 per share; no shares authorized, issued and outstanding as of January 31, 2018; 59,495 shares authorized, 59,465 issued and outstanding with liquidation preference of $230,373 as of January 31, 2017.	0	227,954
Stockholders’ equity (deficit):
Preferred stock, par value $0.0001 per share; 100,000 shares authorized, no shares issued and outstanding as of January 31, 2018 and January 31, 2017.	0	0
Additional paid-in capital	565,653	44,469
Accumulated other comprehensive income (loss)	391	(167)
Accumulated deficit	(402,468)	(287,909)
Total stockholders’ equity (deficit)	163,586	(243,605)
Total liabilities, redeemable convertible preferred stock and stockholders’ equity (deficit)	367,397	130,635
Class A Common Stock
Stockholders’ equity (deficit):
Common stock	7	0
Class B Common Stock
Stockholders’ equity (deficit):
Common stock	$ 3	$ 2

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Statement of Financial Position [Abstract]
Allowance for accounts receivable	$ 1,472	$ 1,306
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	59,494,582
Redeemable convertible preferred stock, shares issued (in shares)	0	59,465,439
Redeemable convertible preferred stock, shares outstanding (in shares)	0	59,465,439
Redeemable convertible preferred stock, liquidation preference	$ 0	$ 230,373
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)		$ 0.0001
Common stock, shares authorized (in shares)		120,000,000
Class A Common Stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,000,000,000	0
Common stock, shares issued (in shares)	70,610,000	0
Common stock, shares outstanding (in shares)	70,609,898	0
Class B Common Stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares issued (in shares)	33,361,000	20,293,000
Common stock, shares outstanding (in shares)	33,361,106	20,229,000

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Revenue
Subscription	$ 239,177	$ 143,136	$ 76,443
Professional services and other	20,813	17,190	9,464
Total revenue	259,990	160,326	85,907
Cost of revenue
Subscription	52,481	34,211	20,684
Professional services and other	28,274	21,738	15,340
Total cost of revenue	80,755	55,949	36,024
Gross profit	179,235	104,377	49,883
Operating expenses
Research and development	70,821	38,659	28,761
Sales and marketing	172,973	118,742	77,915
General and administrative	51,803	30,099	19,195
Total operating expenses	295,597	187,500	125,871
Operating loss	(116,362)	(83,123)	(75,988)
Other income (expense), net	1,682	39	(19)
Loss before provision for (benefit from) income taxes	(114,680)	(83,084)	(76,007)
Provision for (benefit from) income taxes	(321)	425	295
Net loss	$ (114,359)	$ (83,509)	$ (76,302)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (1.38)	$ (4.39)	$ (4.28)
Weighted-average shares used to compute net loss per share attributable to common stockholders, basic and diluted (in shares)	83,004	19,038	17,817

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (114,359)	$ (83,509)	$ (76,302)
Net change in unrealized gains (losses) on available-for-sale securities	(202)	10	(5)
Foreign currency translation adjustments	760	(120)	(42)
Other comprehensive income (loss)	558	(110)	(47)
Comprehensive loss	$ (113,801)	$ (83,619)	$ (76,349)

CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Series F Redeemable Convertible Preferred Stock	Series B Redeemable Convertible Preferred Stock	Redeemable Convertible Preferred Stock	Common Stock Class A Common Stock	Common Stock Class B Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Jan. 31, 2015	53,223,503
Beginning balance at Jan. 31, 2015	$ 154,530
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of redeemable convertible preferred stock (in shares)		6,241,936
Issuance of redeemable convertible preferred stock		$ 73,424
Ending balance (in shares) at Jan. 31, 2016	59,465,439
Ending balance at Jan. 31, 2016	$ 227,954
Beginning balance (in shares) at Jan. 31, 2015					0	18,042,388
Beginning balance at Jan. 31, 2015	(117,198)				$ 0	$ 2	$ 10,908	$ (10)	$ (128,098)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)						1,291,099
Issuance of common stock upon exercise of stock options	1,194						1,194
Issuance of common stock pursuant to charitable donation (in shares)						17,433
Issuance of common stock pursuant to charitable donation	132						132
Repurchases of unvested common stock (in shares)						(25,846)
Vesting of early exercised stock options	1,014						1,014
Stock-based compensation	10,076						10,076
Excess tax benefits from share-based compensation	69						69
Other comprehensive loss	(47)							(47)
Net loss	(76,302)				$ 0	$ (76,302)			(76,302)
Ending balance (in shares) at Jan. 31, 2016					0	19,325,074
Ending balance at Jan. 31, 2016	$ (181,062)				$ 0	$ 2	23,393	(57)	(204,400)
Ending balance (in shares) at Jan. 31, 2017	59,465,439	6,241,936	11,986,055
Ending balance at Jan. 31, 2017	$ 227,954	$ 73,424	$ 16,420
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)						980,074
Issuance of common stock upon exercise of stock options	2,001						2,001
Issuance of common stock pursuant to charitable donation (in shares)						13,935
Issuance of common stock pursuant to charitable donation	129						129
Repurchases of unvested common stock (in shares)						(25,745)
Vesting of early exercised stock options	1,297						1,297
Stock-based compensation	17,649						17,649
Other comprehensive loss	(110)							(110)
Net loss	(83,509)				$ 0	$ (83,509)			(83,509)
Ending balance (in shares) at Jan. 31, 2017					0	20,293,338
Ending balance at Jan. 31, 2017	(243,605)				$ 0	$ 2	44,469	(167)	(287,909)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative-effect adjustment in connection with the adoption of ASU 2016-09	0						200		(200)
Issuance of redeemable convertible preferred stock (in shares)			26,201
Issuance of redeemable convertible preferred stock			$ 408
Conversion of convertible preferred stock to common stock in connection with initial public offering (in shares)				(59,491,640)		59,491,640
Conversion of convertible preferred stock to common stock in connection with initial public offering	$ 228,362			$ (228,362)		$ 6	228,356
Ending balance (in shares) at Jan. 31, 2018	0
Ending balance at Jan. 31, 2018	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock (in shares)					12,650,000
Issuance of stock	$ 194,345				$ 1		194,344
Issuance of common stock upon exercise of stock options (in shares)	9,180,242				8,277,412	902,830
Issuance of common stock upon exercise of stock options	$ 33,363				$ 1		33,362
Issuance of common stock upon net exercise of warrant (in shares)						168,750
Issuance of common stock pursuant to charitable donation (in shares)					24,287	0
Issuance of common stock pursuant to charitable donation	708						708
Issuance of common stock under employee stock purchase plan (in shares)					569,373
Issuance of common stock under employee stock purchase plan	8,369						8,369
Repurchases of unvested common stock (in shares)					(2,813)	(2,313)
Conversion of Class B common stock to Class A common stock (in shares)					49,091,639	(49,091,639)
Conversion of Class B common stock to Class A common stock	0				$ 5	$ (5)
Vesting of early exercised stock options	1,335						1,335
Conversion of convertible preferred stock to common stock in connection with initial public offering (in shares)				(59,491,640)		59,491,640
Conversion of convertible preferred stock to common stock in connection with initial public offering	228,362			$ (228,362)		$ 6	228,356
Issuance of common stock and restricted stock in connection with acquisition (in shares)						1,598,500
Issuance of common stock and restricted stock in connection with acquisition	3,652						3,652
Stock-based compensation	50,858						50,858
Other comprehensive loss	558							558
Net loss	(114,359)				$ (33,293)	$ (81,066)			(114,359)
Ending balance (in shares) at Jan. 31, 2018					70,609,898	33,361,106
Ending balance at Jan. 31, 2018	$ 163,586				$ 7	$ 3	$ 565,653	$ 391	$ (402,468)

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Cash flows from operating activities:
Net loss	$ (114,359)	$ (83,509)	$ (76,302)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation, amortization and accretion	7,001	4,568	2,889
Stock-based compensation	49,860	17,127	9,832
Amortization of deferred commissions	17,584	13,734	8,438
Deferred income taxes	(534)	0	0
Write-off of intangible assets	1,114	0	0
Non-cash charitable contributions	708	0	0
Other, net	719	704	934
Changes in operating assets and liabilities:
Accounts receivable	(18,321)	(11,993)	(10,668)
Deferred commissions	(21,437)	(19,391)	(15,952)
Prepaid expenses and other assets	(10,128)	(3,422)	(1,056)
Accounts payable	3,505	1,529	962
Accrued compensation	3,582	1,967	3,340
Accrued expenses and other liabilities	521	2,387	3,929
Deferred revenue	54,945	34,198	32,118
Net cash used in operating activities	(25,240)	(42,101)	(41,536)
Cash flows from investing activities:
Capitalized internal-use software costs	(5,431)	(5,489)	(2,608)
Purchases of property and equipment	(6,550)	(6,253)	(4,093)
Purchases of securities available for sale	(129,086)	0	(46,360)
Proceeds from maturities and redemption of securities available for sale	39,825	12,500	41,576
Proceeds from sales of securities available for sale	1,538	6,207	12,645
Net cash provided by (used in) investing activities	(99,704)	6,965	1,160
Cash flows from financing activities:
Proceeds from initial public offering, net of underwriters' discounts and commissions	199,948	0	0
Payments of deferred offering costs	(4,038)	(1,584)	0
Proceeds from exercise of stock options, net of repurchases and other	33,646	2,437	3,630
Proceeds from issuance of convertible redeemable preferred stock, net of issuance costs	0	0	73,424
Proceeds from shares issued in connection with employee stock purchase plan	8,369	0	0
Other	(517)	(396)	(213)
Net cash provided by financing activities	237,408	457	76,841
Effects of changes in foreign currency exchange rates on cash, cash equivalents and restricted cash	487	(120)	(42)
Net increase (decrease) in cash, cash equivalents and restricted cash	112,951	(34,799)	36,423
Cash, cash equivalents and restricted cash at beginning of year	23,282	58,081	21,658
Cash, cash equivalents and restricted cash at end of year	136,233	23,282	58,081
Cash paid during the period for:
Income taxes	747	0	0
Non-cash investing and financing activities:
Vesting of early exercised common stock options	1,335	1,297	1,014
Issuance of common stock in connection with warrant exercises	272	0	0
Common stock issued as charitable contribution	708	129	132
Assets acquired under financing arrangement	0	386	853
Deferred offering costs, accrued but not yet paid	0	2,106	368
Property and equipment acquired through tenant improvement allowances	0	1,332	0
Property and equipment and other accrued but not yet paid	111	1,367	317
Issuance of common stock in connection with business combination	2,160	0	0
Conversion of redeemable convertible preferred stock to common stock	228,362	0	0
Reconciliation of cash, cash equivalents, and restricted cash within the 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	$ 21,658

Overview and Basis of Presentation	12 Months Ended
Overview and Basis of Presentation	Jan. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Overview and Basis of Presentation	Overview and Basis of Presentation Description of Business Okta, Inc. (the Company) is the leading provider of identity for the enterprise. The Okta Identity Cloud enables customers to securely connect people to technology, anywhere, anytime and from any device. The Company was incorporated in January 2009 as Saasure, Inc., a California corporation, and was later reincorporated in April 2010 under the name Okta, Inc. as a Delaware corporation. The Company is headquartered in San Francisco, California. Basis of Presentation and Principles of Consolidation The accompanying consolidated financial statements, which include the accounts of the Company and its wholly owned subsidiaries, have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP). All intercompany balances and transactions have been eliminated in consolidation. Certain immaterial reclassifications of prior period amounts have been made in our consolidated balance sheets and consolidated statements of cash flows to conform to the current period presentation. The Company’s fiscal year ends on January 31. References to fiscal 2018, for example, refer to the fiscal year ended January 31, 2018. Initial Public Offering In April 2017, the Company completed an initial public offering (IPO), in which the Company issued and sold 12,650,000 shares of its newly authorized Class A common stock, which included 1,650,000 shares sold pursuant to the exercise by the underwriters’ option to purchase additional shares at a public offering price of $17.00 per share. The Company received aggregate proceeds of $200.0 million from the IPO, net of underwriters’ discounts and commissions, before deducting offering costs of approximately $5.6 million. Immediately prior to the completion of the IPO, all shares of common stock then outstanding were reclassified as Class B common stock, and all shares of redeemable convertible preferred stock then outstanding were converted into 59,491,640 shares of common stock on a one-to-one basis and then reclassified into Class B common stock. See Note 10 for additional details. As of January 31, 2018, 70,609,898 shares of the Company’s Class A common stock and 33,361,106 shares of Class B common stock were outstanding. Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates, judgments and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The Company bases its estimates on historical experience and on other assumptions that its management believes are reasonable under the circumstances. Actual results could vary from those estimates. The Company’s most significant estimates and judgments involve revenue recognition with respect to the determination of the relative selling prices for the Company’s services, determination of the fair value of the Company’s common stock prior to the completion of the IPO, valuation of the Company’s stock-based awards, valuation of deferred income tax assets and contingencies. Foreign Currency The functional currencies of the Company’s foreign subsidiaries are the respective local currencies. Translation adjustments arising from the use of differing exchange rates from period to period are included in accumulated other comprehensive loss within the consolidated statements of redeemable convertible preferred stock and stockholders’ equity (deficit). Foreign currency transaction gains and losses are included in other expense, net in the consolidated statements of operations and were not material for the years ended January 31, 2018, 2017 or 2016. All assets and liabilities denominated in a foreign currency are translated into U.S. dollars at the exchange rate on the balance sheet date. Revenue and expenses are translated at the average exchange rate during the period, and equity balances are translated using historical exchange rates.

Summary of Significant Accounting Policies

12 Months Ended

Jan. 31, 2018

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Segment Information

The Company operates in a single operating segment. The Company’s chief operating decision maker is its chief executive officer, who reviews financial information presented on a consolidated basis for purposes of making operating decisions, assessing financial performance and allocating resources.

Revenue Recognition

The Company derives revenue from subscription fees (which include support fees) and professional services fees. The Company sells subscriptions to its platform through arrangements that are generally one to three years in length. The Company’s arrangements are generally noncancelable and nonrefundable. Furthermore, if a customer reduces the contracted usage or service level, the customer has no right of refund. The Company’s subscription arrangements do not provide customers with the right to take possession of the software supporting the platform and, as a result, are accounted for as service arrangements. This revenue recognition policy is consistent for sales generated directly with customers and sales generated indirectly through our network of independent software vendors, or ISVs, and channel partners.

The Company commences revenue recognition when all of the following criteria are met:


•	There is persuasive evidence of an arrangement;


•	Delivery has occurred;


•	The amount of fees to be paid by the customer is fixed or determinable; and


•	Collection of the fees is reasonably assured.

Subscription Revenue

Subscription revenue, which includes support, is recognized on a straight-line basis over the noncancelable contractual term of the arrangement, generally beginning on the date that the Company’s service is made available to the customer, provided all other revenue recognition criteria have been met.

Professional Services Revenue

The Company’s professional services principally consist of customer specific requests for application integrations, user interface enhancements and other customer specific requests.

Revenue for the Company’s professional services billed on a fixed fee basis are generally recognized when the professional services are completed and professional services arrangements billed on a time and materials basis are recognized as services are performed.

Multiple Element Arrangements

For arrangements with multiple deliverables, the Company evaluates whether the individual deliverables qualify as separate units of accounting. In order to treat deliverables in a multiple deliverable arrangement as separate units of accounting, the deliverables must have stand-alone value upon delivery and, in situations in which a general right of return exists for the delivered item, delivery or performance of the undelivered item is considered probable and substantially within the control of the Company. The Company’s professional services have stand-alone value because the Company has routinely sold these professional services separately. The Company’s subscription services have stand-alone value as the Company routinely sells the subscriptions separately. Customers have no general right of return for delivered items. If the deliverables have stand-alone value upon delivery, the Company accounts for each deliverable separately and revenue is recognized for the respective deliverables as they are delivered based on their relative selling prices, which the Company determines by using the best estimate of selling price (BESP).

The Company has determined its BESP for its deliverables based on customer size, size and volume of the Company’s transactions, overarching pricing objectives and strategies, market and industry conditions, product-specific factors and historical sales of the deliverables.

Deferred Revenue

Deferred revenue consists of customer billings in advance of revenue being recognized from the Company’s subscription and support services and professional services arrangements. The Company primarily invoices its customers for its subscription services arrangements annually in advance. The Company’s payment terms generally provide that customers pay the invoiced portion of the total arrangement fee within 30 days of the invoice date. Amounts anticipated to be recognized within one year of the balance sheet date are recorded as deferred revenue, current; the remaining portion is recorded as deferred revenue, noncurrent in the consolidated balance sheets.

Deferred Commissions

Deferred commissions represent direct and incremental compensation costs incurred in connection with the acquisition of customer contracts. Deferred commissions are initially deferred when earned and amortized over the same period that revenue is recognized for the related noncancelable portion of the subscription arrangement. Amounts anticipated to be recognized within one year of the balance sheet date are recorded as deferred commissions, current; the remaining portion is recorded as deferred commissions, noncurrent in the consolidated balance sheets. Commissions are generally paid within three months of when the subscription arrangement is signed with the customer. Amortization of deferred commissions is included in sales and marketing expense in the consolidated statements of operations.

Cost of Revenue

Costs of revenue primarily consist of costs related to providing the Company’s cloud-based platform to its customers, including third-party hosting fees, amortization of capitalized internal-use software and finite-lived purchased developed technology, customer support, other employee-related expenses for security, technical operations and professional services staff, and allocated overhead costs.

Cash and Cash Equivalents

Cash and cash equivalents consist of cash on hand and highly liquid investments with original maturities of three months or less from the date of purchase. Cash equivalents generally consist of investments in money market funds. The fair market value of cash equivalents approximated their carrying value as of January 31, 2018 and 2017.

Short-term Investments

The Company’s short-term investments comprise asset-backed securities, U.S. treasury securities and corporate debt securities. The Company determines the appropriate classification of its short-term investments at the time of purchase and reevaluates such designation at each balance sheet date. The Company has classified and accounted for its short-term investments as available-for-sale securities as the Company may sell these securities at any time for use in its current operations or for other purposes, even prior to maturity. As a result, the Company classifies its short-term investments, including securities with stated maturities beyond twelve months, within current assets in the consolidated balance sheets.

Available-for-sale securities are recorded at fair value each reporting period. Unrealized gains and losses on these short-term investments are reported as a separate component of accumulated other comprehensive loss in the consolidated balance sheets until realized. Interest income is reported within other income (expense), net in the consolidated statements of operations. The Company periodically evaluates its short-term investments to assess whether those with unrealized loss positions are other-than-temporarily impaired. The Company considers various factors in determining whether to recognize an impairment charge, including the length of time the investment has been in a loss position, the extent to which the fair value is less than the Company’s cost basis, the investment’s financial condition and near-term prospects of the investee. Realized gains and losses are determined based on the specific identification method and are reported in other income (expense), net in the consolidated statements of operations. If the Company determines that the decline in an investment’s fair value is other-than-temporary, the difference is recognized as an impairment loss in the consolidated statements of operations.

Accounts Receivable and Allowances

Accounts receivable are recorded at the invoiced amount, net of allowances. These allowances are based on the Company’s assessment of the collectibility of accounts by considering the age of each outstanding invoice and the collection history of each customer and an evaluation of potential risk of loss associated with delinquent accounts. Amounts deemed uncollectible are recorded to these allowances in the consolidated balance sheets with an offsetting decrease in related deferred revenue and a charge to general and administrative expense in the consolidated statement of operations.

Property and Equipment

Property and equipment, net, is stated at cost less accumulated depreciation. Depreciation is recorded using the straight-line method over the estimated useful lives of the respective assets. Repairs and maintenance costs are expensed as incurred.

The useful lives of property and equipment are as follows:



	Useful lives
Capitalized internal-use software costs	3 years
Computers and equipment	3 years
Furniture and fixtures	7 years
Leasehold improvements	Shorter of 7 years or remaining lease term

Capitalized Internal-Use Software Costs

The Company capitalizes as intangible assets certain costs incurred during the application development stage in connection with software development for its platform. Costs related to preliminary project activities and post-implementation activities are expensed as incurred. Capitalized costs are recorded as part of intangible assets. Maintenance and training costs are expensed as incurred.

Capitalized internal-use software costs are amortized on a straight-line basis over the software’s estimated useful life, which is generally three years. The Company records amortization related to capitalized internal-use software within subscription cost of revenue in the consolidated statements of operations. The Company evaluates the useful lives of these assets on an annual basis and tests for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets.

Business Combinations

When the Company acquires a business, the purchase price is allocated to the net tangible and identifiable intangible assets acquired. Any residual purchase price is recorded as goodwill. The allocation of the purchase price requires management to make significant estimates in determining the fair values of assets acquired and liabilities assumed, especially with respect to intangible assets. These estimates can include, but are not limited to, the cash flows that an asset is expected to generate in the future, the appropriate weighted-average cost of capital and the cost savings expected to be derived from acquiring an asset. These estimates are inherently uncertain and unpredictable. During the measurement period, which may be up to one year from the acquisition date, adjustments to the fair value of these tangible and intangible assets acquired and liabilities assumed may be recorded, with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the fair value of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the consolidated statements of operations.

Goodwill and Other Long-Lived Assets

The excess of the purchase price over the estimated fair value of net assets of businesses acquired in a business combination is recognized as goodwill. Goodwill is tested for impairment annually on November 1^stor more frequently if certain indicators are present.

Long-lived assets, such as property and equipment and finite-lived intangible assets subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of any asset may not be recoverable. Recoverability of assets to be held and used is measured by comparing the carrying amount to the estimated undiscounted future cash flows expected to be generated. If the carrying amount exceeds the undiscounted cash flows, the assets are determined to be impaired and an impairment charge is recognized as the amount by which the carrying amount exceeds its fair value.

The Company amortizes intangible assets with finite lives on a straight-line basis over their estimated useful lives in cost of revenue in the consolidated statements of operations.

Advertising Expenses

Advertising costs are expensed as incurred. Advertising expense was $9.4 million, $4.4 million, and $3.7 million for the years ended January 31, 2018, 2017 and 2016.

Deferred Offering Costs

Deferred offering costs consist primarily of accounting, legal and other fees related to the Company’s IPO. Upon completion of the offering, these costs are offset against the offering proceeds within the consolidated statements of redeemable convertible preferred stock and stockholders’ equity (deficit). As of January 31, 2017 there were $3.7 million, in deferred offering costs in other assets, noncurrent in the consolidated balance sheets. There were no deferred offering costs outstanding as of January 31, 2018.

Stock-Based Compensation

Stock-based compensation issued to employees, including the purchase rights issued under the Company's 2017 Employee Stock Purchase Plan (ESPP), is measured based on the grant-date fair value of the awards and recognized as an expense following the straight-line attribution method over the requisite service period for stock options, restricted stock units (RSUs) and restricted stock, and over the offering period for the purchase rights issued under the ESPP.

The Company’s use of the Black-Scholes option-pricing model to estimate the fair value of stock options granted requires the input of highly subjective assumptions. These assumptions and estimates are as follows:

Fair value — Prior to the IPO, the fair value of the shares of common stock underlying stock options had been established by the Company’s board of directors, which was responsible for these estimates, and had been based in part upon a valuation provided by a third-party valuation firm. Because there had been no public market for the Company’s common stock, its board of directors considered this independent valuation and other factors, including, but not limited to, revenue growth, the current status of the technical and commercial success of its operations, its financial condition, the stage of development and competition to establish the fair value of the Company’s common stock at the time of grant of the option. After the IPO, the Company used the publicly quoted price as reported on the Nasdaq Global Select Market as the fair value of its common stock.

Expected volatility — Expected volatility is a measure of the amount by which the stock price is expected to fluctuate. Since the Company does not have sufficient trading history of its common stock, it estimates the expected volatility of its stock options at their grant date by taking the weighted-average historical volatility of a group of comparable publicly-traded companies over a period equal to the expected life of the options.

Expected term — The Company determines the expected term based on the average period the stock options are expected to remain outstanding, generally calculated as the midpoint of the stock option’s vesting term and contractual expiration period, as the Company does not have sufficient historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior.

Risk-free rate — The Company uses the U.S. Treasury yield that corresponds with the expected term.

Expected dividend yield — The Company utilizes a dividend yield of zero, as it does not currently issue dividends and does not expect to in the future.

Prior to the adoption of ASU 2016-09 on February 1, 2017, the estimated forfeiture rate was based on an analysis of actual forfeitures, analysis of historical and expected future employee turnover behavior and other factors. Furthermore, to the extent the Company’s actual forfeiture rate is different from this estimate, share-based compensation is adjusted accordingly.

Income Taxes

The Company accounts for income taxes in accordance with the liability method of accounting for income taxes. Under this method, the Company recognizes deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax basis of assets and liabilities, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled.

The Company records a valuation allowance to reduce its deferred tax assets to the net amount that the Company believes is more likely than not to be realized. In assessing the need for a valuation allowance, the Company has considered its historical levels of income, expectations of future taxable income and ongoing tax planning strategies. Because of the uncertainty of the realization of the deferred tax assets, the Company has recorded a full valuation allowance against its deferred tax assets. Realization of its deferred tax assets is dependent primarily upon future U.S. taxable income.

The Company recognizes and measures tax benefits from uncertain tax positions using a two-step approach.

The first step is to evaluate the tax position taken or expected to be taken by determining if the weight of available evidence indicates that it is more likely than not that the tax position will be sustained in an audit, including resolution of any related appeals or litigation processes. The second step is to measure the tax benefit as the largest amount that is more than 50% likely to be realized upon ultimate settlement. Significant judgment is required to evaluate uncertain tax positions.

Although the Company believes that it has adequately reserved for its uncertain tax positions, it can provide no assurance that the final tax outcome of these matters will not be materially different. The Company evaluates its uncertain tax position on a regular basis and evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, correspondence with tax authorities during the course of an audit and effective settlement of audit issues.

To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will affect the provision for income taxes in the period in which such determination is made and could have a material impact on the Company’s financial condition and results of operations. The provision for income taxes includes the effects of any accruals that the Company believes are appropriate, as well as the related net interest and penalties.

Facility Leases

Certain facility lease agreements contain rent holidays, allowances and rent escalation provisions. For these leases, the Company recognizes the related rental expense on a straight-line basis over the lease period of the facility and records the difference between amounts charged to operations and amounts paid as deferred rent. These rent holidays, allowances and rent escalations are considered in determining the straight-line expense to be recorded over the lease term.

Concentrations of Risk and Significant Customers

The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents, short-term investments and accounts receivable. Cash and cash equivalents and short-term investments are currently held in two financial institutions and, at times, may exceed federally insured limits.

As of January 31, 2018 and 2017 and for each of the three years ended January 31, 2018, no single customer represented greater than 10% of accounts receivable or greater than 10% of revenue, respectively.

In order to reduce the risk of downtime of the Company’s subscription services, the Company utilizes data center facilities operated by third parties located in Virginia, Oregon, Germany and Ireland. The Company has internal procedures to restore services in the event of disaster at any of its current data center facilities. Even with these procedures for disaster recovery in place, the Company’s subscription services could be significantly interrupted during the time period following a disaster at one of its sites and the subsequent restoration of services at another site.

Geographical Information

Revenue by location is determined by the billing address of the customer. The following table sets forth revenue by geographic area (in thousands):



	Year Ended January 31,
	2018		2017		2016

United States	$	220,382	$	138,925	$	75,583
International	39,608		21,401		10,324
Total	$	259,990	$	160,326	$	85,907

Other than the United States, no individual country exceeded 10% of total revenue for the years ended January 31, 2018, 2017 and 2016. Property and equipment by geographic location is based on the location of the legal entity that owns the asset. As of January 31, 2018 and 2017, substantially all of the Company’s property and equipment was located in the United States.

Net Loss per Share

The Company computes basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. Under the two-class method, basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, less shares subject to repurchase, without consideration for potentially dilutive securities as they do not share in losses. The diluted net loss per share attributable to common stockholders is computed giving effect to all potential dilutive common stock equivalents outstanding for the period. For purposes of this calculation, options to purchase common stock, unvested RSUs, purchase rights issued under the ESPP, shares subject to repurchase from early exercised options, and unvested common stock and restricted stock issued in connection with certain business combinations are considered common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as the effect is antidilutive. Since the Company's IPO, Class A and Class B common stock are the only outstanding equity of the Company. The rights of the holders of Class A and Class B common stock are identical, except with respect to voting and conversion rights. See Note 10.

Recently Adopted Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board (FASB) issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) (ASU 2014-09) and has modified the standard thereafter. The standard replaces existing revenue recognition rules with a comprehensive revenue measurement and recognition standard and expanded disclosure requirements. ASU 2014-09, as amended, becomes effective for the Company on February 1, 2018. The standard permits the use of either the retrospective or modified retrospective transition method. Under the retrospective transition method, the standard applies to contracts in all reporting periods presented. Under the modified retrospective transition method, the standard applies only to contracts still open as of February 1, 2018, recognizing in beginning retained earnings an adjustment for the cumulative effect of the change and providing additional disclosures comparing results to previous standards.

The new standard will impact the following policies and disclosures:


•	removal of the current limitation on contingent revenue will result in revenue being recognized earlier for certain contracts;


•	revenue for all professional services will be recognized based on proportional performance;


•	required disclosures including information about the transaction price allocated to remaining performance obligations and related timing of revenue recognition; and


•	accounting for deferred commissions including expanding the costs that qualify for deferral and increasing the amortization period beyond the initial contract to include anticipated renewals.

On February 1, 2018, the Company adopted the requirements of Topic 606 using the retrospective transition method. The impact of adopting the new standard on the Company's fiscal 2018 and fiscal 2017 revenues is not material. The primary impact of adopting the new standard relates to the deferral of incremental commission costs of obtaining subscription contracts. Under Topic 605, the Company deferred only direct and incremental commission costs to obtain a contract and amortized those costs on a straight-line basis over the noncancelable term of the related subscription contract, which was generally one to three years. Under the new standard, the Company defers all incremental commission costs to obtain the contract. The Company amortizes these costs on a straight-line basis over a period of benefit, determined to be five years.

Select consolidated statement of operations line items, which reflect the adoption of the new standard are as follows (in millions, except per share data):



	Year Ended January 31,
	2018									2017
	As Reported			Adoption of ASU 2014-09			As Adjusted			As Reported			Adoption of ASU 2014-09			As Adjusted
Revenue
Subscription	$	239.2		$	(1.2	)	$	238.0		$	143.1		$	1.9		$	145.0
Professional services and other	20.8			(0.7		)	20.1			17.2			(2.1		)	15.1
Total revenue	260.0			(1.9		)	258.1			160.3			(0.2		)	160.1
Sales and marketing	173.0			(8.0		)	165.0			118.7			(8.0		)	110.8
Total operating expenses	295.6			(8.0		)	287.6			187.5			(8.0		)	179.5
Net loss	(114.4		)	6.1			(108.3		)	(83.5		)	7.8			(75.7		)
Net loss per share, basic and diluted	(1.38		)	0.08			(1.30		)	(4.39		)	0.41			(3.98		)

Select consolidated balance sheet line items, which reflect the adoption of the new standard are as follows (in millions):



	As of January 31, 2018									As of January 31, 2017
	As Reported			Adoption of ASU 2014-09			As Adjusted			As Reported			Adoption of ASU 2014-09			As Adjusted
Assets
Current assets:
Deferred commissions	$	16.5		$	1.3		$	17.8		$	13.5		$	(0.3	)	$	13.2
Prepaid expenses and other current assets	17.0			0.4			17.4			7.0			1.3			8.3
Total current assets	315.4			1.7			317.1			92.8			1.0			93.8
Deferred commissions, noncurrent	11.0			29.8			40.8			10.1			23.4			33.5
Total assets	$	367.4		$	31.5		$	398.9		$	130.6		$	24.4		$	155.0

Liabilities and stockholders’ equity (deficit)
Deferred revenue	$	162.6		$	(3.3	)	$	159.3		$	108.0		$	(3.9	)	$	104.1
Total current liabilities	190.8			(3.3		)	187.5			134.5			(3.9		)	130.6
Deferred revenue, noncurrent	6.0			(0.7		)	5.3			5.7			(1.0		)	4.7
Total liabilities	203.8			(4.0		)	199.8			146.3			(5.0		)	141.3
Accumulated deficit	(402.5		)	35.5			(367.0		)	(287.9		)	29.4			(258.5		)
Total stockholders’ equity (deficit)	$	163.6		$	35.5		$	199.1		$	(243.6	)	$	29.4		$	(214.2	)

Adoption of the standards related to revenue recognition had no impact to cash provided by or used in operating, financing, or investing activities on our consolidated cash flows statements. Additionally, the adoption of the standards did not have a material impact on taxes. The adoption adjustments impacted the deferred taxes pertaining to the U.S. entity which are subject to a full valuation allowance.

In January 2016, the FASB issued ASU No. 2016-01 (Subtopic 825-10), Financial Instruments Overall: Recognition and Measurement of Financial Assets and Financial Liabilities (ASU 2016-01), which primarily affects the accounting for equity investments, financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. In addition, the FASB clarified guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on available-for-sale debt securities. The accounting for other financial instruments, such as loans, investments in debt securities and financial liabilities is largely unchanged. ASU 2016-01 is effective for fiscal years beginning after December 15, 2017 and interim periods in fiscal years beginning after December 15, 2018. Early adoption is permitted. The Company adopted ASU 2016-01 as of the beginning of its fiscal year ended January 31, 2018. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements.

In March 2016, the FASB issued Accounting Standards Update (ASU) No. 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. This new guidance was intended to simplify several areas of accounting for stock-based compensation arrangements, including the accounting for income taxes, the classification of excess tax benefits on the statement of cash flows and the accounting for forfeitures. This guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. The Company adopted this guidance as of the beginning of its fiscal year ended January 31, 2018. The new guidance allows entities to account for forfeitures as they occur. The Company elected to account for forfeitures as they occur and adopted this provision on a modified retrospective basis. An adjustment of $0.2 million representing cumulative prior years’ impact was recognized as an adjustment to decrease retained earnings in the period of adoption. The amendments related to the accounting for income taxes and classification of excess tax benefits on the statement of cash flows were adopted prospectively. Adoption of all other changes in the new guidance did not have a significant impact on the Company's consolidated financial statements.

In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805) Clarifying the Definition of a Business (ASU 2017-01), which amends the guidance of FASB Accounting Standards Codification Topic 805, “Business Combinations,” adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions or disposals of assets or businesses. The definition of a business affects many areas of accounting including acquisitions, disposals, goodwill, and consolidation. This guidance is effective for annual and interim periods beginning after December 15, 2017, and early adoption is permitted under certain circumstances. The Company early adopted this guidance as of the beginning of its fiscal year ended January 31, 2018. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements.

In January 2017, the FASB issued ASU No. 2017-04, Simplifying the Test for Goodwill Impairment (ASU 2017-04), which removes the second step of the goodwill impairment test that requires a hypothetical purchase price allocation. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. This guidance is effective for interim and annual reporting periods beginning after December 15, 2019 and will be applied prospectively. Early adoption is permitted for annual or any interim impairment tests with a measurement date on or after January 1, 2017. The Company early adopted this guidance as of the beginning of its fiscal year ended January 31, 2018. In November 2017, the Company performed an annual goodwill impairment review by comparing the fair value of its reporting unit with its carrying amount. Based on the annual assessment, no indicator of impairment was noted and as such no impairment charge was recorded during the year ended January 31, 2018. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements.

In May 2017, the FASB issued ASU No. 2017-09, Compensation—Stock Compensation (Topic 718) Scope of Modification Accounting (ASU 2017-09), which clarifies which changes to the terms or conditions of a share-based payment award are subject to the guidance on modification accounting. Entities would apply the modification accounting guidance unless the value, vesting requirements and classification of a share-based payment award are the same immediately before and after a change to the terms or conditions of the award. This guidance is effective for annual and interim periods beginning after December 15, 2017, and will be applied prospectively to awards modified on or after the effective date. The Company early adopted this guidance as of the beginning of its fiscal year ended January 31, 2018. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements.

Recent Accounting Pronouncements Not Yet Adopted

In February 2016, the FASB issued ASU No. 2016-02 (Topic 842), Leases (ASU 2016-02), which supersedes the guidance in topic ASC 840, Leases. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases today. Under the standard, disclosures are required to meet the objective of enabling users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The Company will be required to recognize and measure leases existing at, or entered into after, the beginning of the earliest comparative period presented using a modified retrospective approach, with certain practical expedients available. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements.

In February 2018, the FASB issued ASU No. 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (ASU 2018-02). Under existing U.S. GAAP, the effects of changes in tax rates and laws on deferred tax balances are recorded as a component of income tax expense in the period in which the law was enacted. When deferred tax balances related to items originally recorded in accumulated other comprehensive income (loss) are adjusted, certain tax effects become stranded in accumulated other comprehensive income. The amendments in ASU 2018-02 allow a reclassification from accumulated other comprehensive income (loss) to retained earnings (accumulated deficit) for stranded income tax effects resulting from the 2017 Tax Cuts and Jobs Act. The amendments in this ASU also require certain disclosures about stranded income tax effects. The guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption in any period is permitted. The Company’s provisional adjustments recorded in FY18 to account for the impact of the 2017 Tax Cuts and Jobs Act did not result in stranded tax effects. The Company does not anticipate the adoption of this standard will have a material impact on the Company's consolidated financial statements.

Acquisition	12 Months Ended
Acquisition	Jan. 31, 2018
Business Combinations [Abstract]
Acquisition	Acquisition Stormpath On February 17, 2017, the Company acquired the rights to hire certain employees and a non-exclusive intellectual property license from Stormpath, Inc. (Stormpath), a privately-held technology company which had built a user management and authentication service for software development teams. The transaction has been accounted for as a business combination and is expected to enhance the Company’s product offerings and service by leveraging the talents of the engineering teams. The total consideration of $3.7 million, consisting of 200,000 shares of common stock valued at $2.2 million issued to Stormpath and replacement awards valued at $1.5 million issued to the hired employees, was recognized as goodwill. See Note 11 for further details on replacement awards issued in this transaction. Goodwill is not deductible for tax purposes. Pro forma results of operations for the transaction have not been presented as they were not material to the consolidated statements of operations. In addition, the Company issued an incremental 800,000 shares of restricted common stock valued at $8.6 million to Stormpath in connection with the transaction. These shares of restricted common stock will vest ratably on the first and second anniversaries of the transaction date upon achieving the respective performance conditions, including the continued employment of certain employees with Okta and the wind down of the Stormpath, Inc. entity. The aggregate fair value of the shares of restricted common stock, as determined on the date of the transaction, will be recognized as post-combination stock-based compensation in the statement of operations over two years based on an accelerated attribution method. See Note 11 for further details.

Cash Equivalents and Short-term Investments

12 Months Ended

Jan. 31, 2018

Investments, Debt and Equity Securities [Abstract]

Cash Equivalents and Short-term Investments

The amortized costs, unrealized gains and losses and estimated fair values of the Company’s cash equivalents and short-term investments as of January 31, 2018 and 2017 were as follows (in thousands):



	As of January 31, 2018
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash equivalents:
Money market funds	$	90,770	$	—	$	—		$	90,770
Total cash equivalents	$	90,770	$	—	$	—		$	90,770
Short-term investments:
Commercial paper	$	15,946	$	—	$	—		$	15,946
U.S. treasury securities	61,896		—		(158		)	61,738
Corporate debt securities	24,125		—		(44		)	24,081
Total short-term investments	101,967		—		(202		)	101,765
Total	$	192,737	$	—	$	(202	)	$	192,535



	As of January 31, 2017
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash equivalents:
Money market funds	$	10,565	$	—	$	—		$	10,565
Total cash equivalents	$	10,565	$	—	$	—		$	10,565
Short-term investments:
Asset-backed securities	$	1,538	$	—	$	—		$	1,538
Corporate debt securities	12,842		13		(3		)	12,852
Total short-term investments	14,380		13		(3		)	14,390
Total	$	24,945	$	13	$	(3	)	$	24,955

All short-term investments were designated as available-for-sale securities as of January 31, 2018 and 2017.

The following tables present the contractual maturities of the Company’s short-term investments as of January 31, 2018 and 2017 (in thousands):



	As of January 31, 2018				As of January 31, 2017
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due within one year	$	93,421	$	93,237	$	12,842	$	12,852
Due between one to five years	8,546		8,528		1,538		1,538
	$	101,967	$	101,765	$	14,380	$	14,390

The Company had 23 and five short-term investments in unrealized loss positions as of January 31, 2018 and 2017, respectively. There were no material gross unrealized gains or losses from available-for-sale securities and no material realized gains or losses from available-for-sale securities that were reclassified out of accumulated other comprehensive income for the years ended January 31, 2018, 2017 or 2016.

For available-for-sale debt securities that have unrealized losses, the Company evaluates whether (i) it has the intention to sell any of these investments and (ii) whether it is not more likely than not that it will be required to sell any of these available-for-sale debt securities before recovery of the entire amortized cost basis. Based on this evaluation, the Company determined that there were no other-than-temporary impairments associated with short-term investments as of January 31, 2018 and 2017.

Fair Value Measurements

12 Months Ended

Jan. 31, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company measures its financial assets at fair value each reporting period using a fair value hierarchy that prioritizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. A financial instrument’s classification within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Three levels of inputs maybe used to measure as follows:

Level 1-Valuations based on observable inputs that reflect quoted prices for identical assets or liabilities in active markets.

Level 2-Valuations based on other inputs that are directly or indirectly observable in the marketplace.

Level 3-Valuations based on unobservable inputs that are supported by little or no market activity.

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table presents information about the Company’s financial assets that are measured at fair value on a recurring basis using the above input categories (in thousands):



	As of January 31, 2018
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	90,770	$	—	$	—	$	90,770
Total cash equivalents	$	90,770	$	—	$	—	$	90,770
Short-term investments:
Commercial paper	$	—	$	15,946	$	—	$	15,946
U.S. treasury securities	—		61,738		—		61,738
Corporate debt securities	—		24,081		—		24,081
Total short-term investments	—		101,765		—		101,765
Total cash equivalents and short-term investments	$	90,770	$	101,765	$	—	$	192,535



	As of January 31, 2017
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	10,565	$	—	$	—	$	10,565
Total cash equivalents	$	10,565	$	—	$	—	$	10,565
Short-term investments:
Asset-backed securities	$	—	$	1,538	$	—	$	1,538
Corporate debt securities	—		12,852		—		12,852
Total short-term investments	—		14,390		—		14,390
Total cash equivalents and short-term investments	$	10,565	$	14,390	$	—	$	24,955
Liabilities:
Series B redeemable convertible preferred stock warrant	$	—	$	—	$	304	$	304

During the three months ended April 30, 2017, the Series B redeemable convertible preferred stock warrant liability that was outstanding as of January 31, 2017 was exercised. The corresponding warrant liability was remeasured to fair value based upon the value of the underlying common stock issued at the IPO and reclassified to additional paid-in capital. The expense resulting from remeasurement was recognized in other income (expense), net in the consolidated statements of operations.

The change in the fair value of the Series B redeemable convertible preferred stock warrant was as follows (in thousands):



Balance at January 31, 2016	$	237
Increase in fair value of warrant	67
Balance at January 31, 2017	304
Increase in fair value of warrant	104
Reclassification of remaining warrant liability to additional paid-in capital	(408		)
Balance at January 31, 2018	$	—

During the years ended January 31, 2018, 2017 and 2016, the Company had no transfers between levels of the fair value hierarchy of its assets measured at fair value.

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The carrying amounts of certain financial instruments, including cash held in banks, accounts receivable and accounts payable approximate fair value due to their short-term maturities and are excluded from the fair value table above.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Goodwill and Intangible Assets, net

12 Months Ended

Jan. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets, net

Goodwill

During the three months ended April 30, 2017, the Company recorded $3.7 million of goodwill related to its transaction with Stormpath (see Note 3). No goodwill impairments were recorded during the years ended January 31, 2018, 2017 and 2016.

Goodwill balances as of January 31, 2018 and 2017 were as follows (in thousands):




Balance as of January 31, 2017	$	2,630
Goodwill recorded in connection with Stormpath acquisition	3,652
Balance as of January 31, 2018	$	6,282

Intangible Assets, net

Intangible assets consisted of the following (in thousands):



	As of January 31, 2018
	Gross		Accumulated Amortization			Write-offs			Net
Capitalized internal-use software costs	$	17,511	$	(5,172	)	$	(1,077	)	$	11,262
Software licenses	1,094		(558		)	(37		)	499
Purchased developed technology	570		(570		)	—			—
	$	19,175	$	(6,300	)	$	(1,114	)	$	11,761



	As of January 31, 2017
	Gross		Accumulated Amortization			Write-offs		Net
Capitalized internal-use software costs	$	10,859	$	(2,487	)	$	—	$	8,372
Software licenses	1,093		(314		)	—		779
Purchased developed technology	570		(566		)	—		4
	$	12,522	$	(3,367	)	$	—	$	9,155

The Company capitalized $6.7 million and $6.1 million of internal-use software during the years ended January 31, 2018 and 2017, respectively, which included $1.2 million and $0.6 million of stock-based compensation costs, respectively. Amortization expense of capitalized internal-use software costs totaled $2.7 million, $1.6 million and $0.7 million during the years ended January 31, 2018, 2017 and 2016, respectively. The Company reversed $1.1 million of previously capitalized costs in the year ended January 31, 2018 as they were not realizable. The charge was recognized in research and development in the consolidated statements of operations.

The Company acquired $0.4 million of software licenses to support its operations in the year ended January 31, 2017 and did not acquire software licenses in the year ended January 31, 2018.

Amortization expense of intangible assets for the years ended January 31, 2018, 2017 and 2016 was $2.9 million, $1.8 million, and $0.9 million, respectively.

As of January 31, 2018, estimated remaining amortization expense for the intangible assets by fiscal year is as follows (in thousands):



2019	$	2,954
2020	1,943
2021	6,864
Total	$	11,761

- Definition

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

+ References + Details

Balance Sheet Components

12 Months Ended

Jan. 31, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Components

Property and Equipment, net

Property and equipment consisted of the following (in thousands):



	As of January 31,
	2018			2017

Computers and equipment	$	5,384		$	3,753
Furniture and fixtures	7,083			4,204
Leasehold improvements	8,188			7,175
Property and equipment, gross	20,655			15,132
Less accumulated depreciation	(8,115		)	(4,106		)
Property and equipment, net	$	12,540		$	11,026

Depreciation expense was $4.0 million, $2.4 million and $1.1 million for the years ended January 31, 2018, 2017 and 2016, respectively.

Allowances

The Company’s allowances for the years ended January 31, 2018, 2017 and 2016 are as follows (in thousands):



	As of January 31,
	2018			2017			2016

Balance, beginning of period	$	1,306		$	861		$	117
Additions	431			1,185			979
Write-offs	(265		)	(740		)	(235		)
Balance, end of period	$	1,472		$	1,306		$	861

Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):



	As of January 31,
	2018		2017

Deposit related to early exercise of unvested options	$	1,119	$	2,168
Accrued expenses	3,389		4,297
Redeemable convertible preferred stock warrant liability	—		304
Accrued taxes payable	835		826
Deferred rent, current	520		225
Other	324		543
Accrued expenses and other current liabilities	$	6,187	$	8,363

Other Liabilities, noncurrent

Other liabilities, noncurrent consisted of the following (in thousands):



	As of January 31,
	2018		2017

Deferred rent, noncurrent	$	5,010	$	4,615
Deferred tax liabilities	175		132
Other	1,832		1,332
Other liabilities, noncurrent	$	7,017	$	6,079

Debt	12 Months Ended
Debt	Jan. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt Loan and Security Agreement On March 10, 2014, the Company entered into a line of credit and term loan agreement with Silicon Valley Bank (SVB) in the amount of $5 million and $10.0 million, respectively. On June 17, 2015, the Company expanded its line of credit from $5.0 million to $20.0 million and extended the term by one year to mature on March 10, 2017. On November 21, 2016, the Company amended the agreement to extend the maturity date to November 21, 2018 and increase the borrowing capacity of the line of credit (Revolving Line) to $40.0 million. The available amount, not to exceed $40.0 million, is based on certain revenue metrics and is reduced by letters of credit totaling $4.2 million as of January 31, 2018 established in connection with facility lease agreements. As of January 31, 2018, $35.8 million was available under the Revolving Line. Proceeds from loans made under the Revolving Line may be borrowed, repaid and reborrowed until November 21, 2018. Repayment of any outstanding proceeds are payable on November 21, 2018, but may be prepaid without penalty. Borrowings under the Revolving Line bear interest at an annual rate based on the one-year Prime rate plus a spread of 0.75%. Interest is payable quarterly. The Company is required to pay a quarterly facility fee to SVB of 0.15% per annum on the average undrawn portion available under the facility plus balances of outstanding letters of credits. Additionally, the Company is required to pay an upfront, one-time, commitment fee of $0.1 million and annual anniversary fees of $0.1 million on the amendment’s first and second anniversary dates. As of January 31, 2018 and 2017, no amounts had been drawn under the Revolving Line and the Company was in compliance with all covenants pursuant to the loan and security agreement. As part of the initial loan agreement, upon closing, the Company granted SVB a warrant to purchase 187,500 shares of common stock at $1.40 per share, with a potential to acquire up to an additional 112,500 shares of common stock at the same price, which right would be triggered upon future amounts drawn under the loan agreement. No additional amounts were drawn under the credit facility and as such, the conditional warrant to acquire up to an additional 112,500 shares was not issued. The fair value of the common stock warrant at the time of issuance was recorded as debt issuance costs. Upon exercise of the warrant in March 2017 in conjunction with the IPO, 168,750 shares were issued and 18,750 shares were withheld by the Company in lieu of cash exercise.

Commitments and Contingencies

12 Months Ended

Jan. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Leases

The Company leases office space under noncancelable operating leases for its San Francisco, California headquarters, as well as its offices in various cities in the United States, United Kingdom, Australia and Canada. These office leases expire on various dates through October 2028.

These leases include a nine-year lease in San Francisco for which the Company is entitled to receive tenant incentives of $1.8 million, all of which was received as of January 31, 2017. Leasehold improvements associated with this lease are being amortized over its lease term.

In December 2017, the Company entered into an office lease in San Francisco expected to become the Company’s new corporate headquarters. This lease has a 10 year term, which is expected to expire in October 2028. The Company is entitled to two five-year options to extend this lease, subject to certain requirements. The total commitment is $206.3 million with a tenant improvement allowance of up to $24.7 million. The Company secured the lease obligation with an $8 million letter of credit, which is designated as restricted cash and included in other assets on its consolidated balance sheet as of January 31, 2018.

In August 2017, the Company executed an amendment to its San Jose lease to add space and to extend the lease term through August 2024. The incremental commitment for the additional space is $6.6 million with a tenant improvement allowance of up to $0.8 million. Rental payments will commence in March 2018.

As of January 31, 2018, the future minimum lease payments by fiscal year under various operating leases and purchase obligations, such as data center operations and sales and marketing activities, are as follows (in thousands):



	Operating Leases		Purchase Obligations		Total
2019	$	14,105	$	13,048	$	27,153
2020	18,243		13,077		31,320
2021	24,719		4,347		29,066
2022	26,521		—		26,521
2023	26,487		—		26,487
Thereafter	144,386		—		144,386
Total contractual obligations	$	254,461	$	30,472	$	284,933

Deferred rent was $5.5 million and $4.8 million as of January 31, 2018 and 2017, respectively, and is included in accrued expenses and other current liabilities and other liabilities, noncurrent in the consolidated balance sheets. Rent expense was $10.6 million, $7.4 million and $5.2 million for the years ended January 31, 2018, 2017 and 2016, respectively.

In conjunction with the execution of the leases, letters of credit in the aggregate amount of $12.2 million and $5.4 million were issued and outstanding as of January 31, 2018 and 2017, respectively. No draws have been made under such letters of credit.

Legal Matters

From time to time in the normal course of business, the Company may be subject to various legal matters such as threatened or pending claims or proceedings. There were no material such matters as of January 31, 2018 and 2017.

Warranties and Indemnification

The Company’s subscription services are generally warranted to perform materially in accordance with the Company’s online help documentation under normal use and circumstances. Additionally, the Company’s arrangements generally include provisions for indemnifying customers against liabilities if its subscription services infringe a third party’s intellectual property rights. Furthermore, the Company may also incur liabilities if it breaches the security or confidentiality obligations in its arrangements. To date, the Company has not incurred significant costs and has not accrued a liability in the accompanying consolidated financial statements as a result of these obligations.

The Company has entered into service-level agreements with a majority of its customers defining levels of uptime reliability and performance and permitting those customers to receive credits for prepaid amounts related to unused subscription services if the Company fails to meet the defined levels of uptime. In very limited instances, the Company allows customers to early terminate their agreements in the event that the Company fails to meet those levels as they may constitute a breach of contract. If the customer did terminate, they would receive a refund of prepaid unused subscription fees. To date, the Company has not experienced any significant failures to meet defined levels of uptime reliability and performance as a result of those agreements and, as a result, the Company has not accrued any liabilities related to these agreements in the consolidated financial statements.

Common Stock and Stockholders' Equity (Deficit)

12 Months Ended

Jan. 31, 2018

Equity [Abstract]

Common Stock and Stockholders' Equity (Deficit)

Redeemable Convertible Preferred Stock

Immediately prior to the completion of the IPO in April 2017, all shares of redeemable convertible preferred stock then outstanding were converted into 59,491,640 shares of common stock on a one-to-one basis and then immediately reclassified into Class B common stock and additional paid-in capital. As of January 31, 2018, there were no shares of redeemable convertible preferred stock issued and outstanding.

The authorized, issued and outstanding shares of redeemable convertible preferred stock (Preferred Stock) and liquidation preferences as of January 31, 2017 were as follows:



Series	Authorized Shares	Issued and Outstanding Shares	Liquidation Preference		Carrying Value
Series A	14,210,789	14,210,783	$	11,373,000	$	11,322,000
Series B	12,015,123	11,986,055	16,500,000		16,420,000
Series C	10,708,782	10,708,780	25,000,000		24,872,000
Series D	6,833,654	6,833,651	27,500,000		27,416,000
Series E	9,484,234	9,484,234	75,000,000		74,500,000
Series F	6,242,000	6,241,936	75,000,000		73,424,000
	59,494,582	59,465,439	$	230,373,000	$	227,954,000

Series B Redeemable Convertible Preferred Stock Warrant

As of January 31, 2017, there was an outstanding warrant to purchase 29,058 shares of Series B redeemable convertible Preferred Stock at $1.38 per share (Series B warrant). The fair value of the Series B warrant was $0.3 million as of January 31, 2017. The Series B warrant was net exercised at the IPO price immediately following the completion of the Company's IPO in April 2017, and was reclassified to additional paid-in capital.

Common Stock

Immediately prior to the completion of the IPO, all shares of common stock then outstanding were reclassified into Class B common stock. Shares offered and sold in the IPO consisted of the newly authorized shares of Class A common stock.

As of January 31, 2018, the Company had authorized 1,000,000,000 shares of Class A common stock and had authorized 120,000,000 shares of Class B common stock, each with par value $0.0001 per share. As of January 31, 2017, the Company had authorized 120,000,000 shares of common stock with par value $0.0001 per share. As of January 31, 2018, 70,609,898 shares of Class A common stock and 33,361,106 shares of Class B common stock were issued and outstanding. Holders of Class A and Class B common stock are entitled to one vote per share and 10 votes per share, respectively, and the shares of Class A common stock and Class B common stock are identical, except for voting and conversion rights. Shares of Class B common stock may be converted into Class A common stock at any time at the option of the stockholder on a one-for-one basis, and are automatically converted into Class A common stock upon sale or transfer, subject to certain limited exceptions. Shares of Class A common stock are not convertible.

As of January 31, 2018, shares of common stock reserved for future issuance are as follows:




Options and unvested RSUs outstanding	27,779,974
Available for future stock option and RSU grants	9,842,925
Available for ESPP	2,430,627
	40,053,526

Awards Issued as Charitable Contributions

During the year ended January 31, 2018, the Company issued 24,287 shares of Class A common stock as charitable contributions and recognized $0.7 million as general and administrative expense in the consolidated statement of operations. During the years ended January 31, 2017 and 2016, the Company issued 13,935 and 17,433 shares, respectively, of Class B common stock as charitable contributions and recognized $0.1 million for both respective periods as general and administrative expense in the consolidated statement of operations.

Employee Incentive Plans

12 Months Ended

Jan. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Employee Incentive Plans

The Company’s equity incentive plans provide for granting stock options, RSUs and restricted stock awards to employees, consultants, officers and directors. In addition, the Company offers an ESPP to eligible employees.

Stock-based compensation expense by award type was as follows (in thousands):



	Year Ended January 31,
	2018		2017		2016
Stock options	$	24,186	$	17,127	$	9,832
RSUs	9,104		—		—
ESPP	7,111		—		—
Restricted stock awards	3,281		—		—
Restricted common stock	6,178		—		—
Total	$	49,860	$	17,127	$	9,832

Stock-based compensation expense was recorded in the following cost and expense categories in the Company’s consolidated statements of operations (in thousands):



	Year Ended January 31,
	2018		2017		2016
Cost of revenue:
Subscription	$	4,600	$	1,979	$	909
Professional services and other	3,137		1,283		553
Research and development	18,107		2,992		1,748
Sales and marketing	13,242		6,029		2,853
General and administrative	10,774		4,844		3,769
Total	$	49,860	$	17,127	$	9,832

Stock-based compensation expense recorded to research and development in the consolidated statements of operations exclude amounts that were capitalized related to internal-use software for the years ended January 31, 2018, 2017 and 2016. Refer to Note 6 for additional details.

Equity Incentive Plans

The Company has two equity incentive plans: the 2009 Stock Plan (2009 Plan) and the 2017 Equity Incentive Plan (2017 Plan). Upon the completion of the Company’s IPO in April 2017, the Company ceased granting equity under the 2009 Plan, and all shares that remained available for future issuance under the 2009 Plan at that time were transferred to the 2017 Plan. As of January 31, 2018, options granted under the 2009 Plan to purchase 24,836,949 shares of Class B common stock remain outstanding, and options granted under the 2017 Plan to purchase 80,096 shares of Class A common stock remain outstanding. As of January 31, 2018, the total number of shares reserved for future Class A stock grants under the 2017 Plan was 9,842,925 shares, including shares transferred from the 2009 Plan.

Stock Options

Options issued to new employees under the Plan generally are exercisable for periods not to exceed ten years and generally vest over four years with 25% vesting after one year and with the remainder vesting monthly thereafter in equal installments. Shares offered under the Plan may be: (i) authorized but unissued shares or (ii) treasury shares.

A summary of the Company’s stock option activity and related information is as follows:



	Number of Options		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding as of January 31, 2017	32,866,862		$	6.01	8.2	$	145,570
Granted	2,676,667		11.56
Exercised	(9,180,242	)	3.66
Canceled	(1,446,242	)	7.76
Outstanding as of January 31, 2018	24,917,045		$	7.37	7.6	$	550,173
As of January 31, 2018:
Vested and expected to vest	24,917,045		$	7.37	7.6	$	550,173
Vested and exercisable	10,205,493		$	5.33	6.9	$	246,189

The weighted-average grant-date fair value of options granted was $5.40, $4.00 and $3.14 during the years ended January 31, 2018, 2017 and 2016, respectively. The total grant-date fair value of stock options vested was $23.9 million, $13.1 million and $7.7 million during the years ended January 31, 2018, 2017 and 2016, respectively. The intrinsic value of the options exercised, which represents the difference between the fair market value of the Company’s common stock on the date of exercise and the exercise price of each option, was $204.8 million, $6.9 million and $4.8 million for the years ended January 31, 2018, 2017 and 2016, respectively.

As of January 31, 2018, there was a total of $53.9 million of unrecognized stock-based compensation expense, which is expected to be recognized over a weighted-average period of 2.6 years.

The Company used the Black-Scholes option pricing model to estimate the fair value of stock options granted with the following assumptions:



	Year Ended January 31,
	2018	2017	2016
Expected volatility	40% - 41%	40% - 44%	42% - 46%
Expected term (in years)	6.3 - 6.4	5.5 - 6.9	5.0 - 6.1
Risk-free interest rate	1.87% - 2.21%	1.13% - 2.28%	1.43% - 1.88%
Expected dividend yield	—	—	—

Options Subject to Early Exercise

Prior to the IPO, at the discretion the Company's board of directors, certain options were exercisable immediately at the date of grant but are subject to a repurchase right, under which the Company may buy back any unvested shares at their original exercise price in the event of an employee’s termination prior to full vesting. The consideration received for an exercise of an unvested option is considered to be a deposit of the exercise price and the related dollar amount is recorded as a liability. The liabilities are reclassified into equity as the awards vest. As of January 31, 2018 and 2017, the Company had $1.1 million and $2.2 million, respectively, recorded in accrued expenses and other current liabilities related to early exercises of options to acquire 187,820 and 467,180 shares of Class B common stock, respectively.

Restricted Stock Units

A summary of the Company’s RSU activities and related information is as follows:



	Number of RSUs		Weighted- Average Grant Date Fair Value Per Share
Outstanding as of January 31, 2017	—		$	—
Granted	3,012,111		24.37
Vested	—		—
Forfeited	(149,182	)	24.15
Outstanding as of January 31, 2018	2,862,929		$	24.38

The Company granted 3,012,111 RSUs with an aggregate fair value of $73.4 million for the year ended January 31, 2018. As of January 31, 2018, all outstanding RSUs are unvested and there was $60.4 million of unrecognized stock-based compensation expense related to unvested RSUs, which is expected to be recognized over a weighted-average period of 3.5 years based on vesting under the award service conditions.

Equity Awards Issued in Connection with Business Combinations

In connection with the Stormpath transaction, the Company issued 800,000 shares of restricted common stock to Stormpath with an aggregate fair value of $8.6 million to be recognized as post combination stock-based compensation. The restricted common stock will vest ratably on the first and second anniversaries of the transaction date upon achievement of the respective performance conditions, including the continued employment of certain employees with the Company and the wind down of the Stormpath, Inc. entity. The stock-based compensation expense related to the restricted common stock has a requisite service period of two years and will be recognized using an accelerated attribution method due to the existence of performance conditions.

As of January 31, 2018, there was $2.5 million of unrecognized compensation expense related to this restricted common stock which is expected to be recognized over the remaining weighted average life of 1.0. These shares of restricted common stock were separately authorized by the Company’s board of directors, and did not reduce the number of shares available for future issuance under the 2009 Plan or the 2017 Plan.

The Company separately entered into retention arrangements with certain employees of Stormpath and issued 598,500 restricted stock awards under the 2009 Plan with an aggregate fair value of $6.6 million with performance conditions, including continued employment of certain employees with the Company and the wind down of the Stormpath, Inc. entity. The restricted stock awards will vest ratably over two or three years from the transaction date. Additionally, the Company granted 518,900 service-based stock options under the 2009 Plan to certain Stormpath employees with an aggregate fair value of $2.5 million to vest ratably over the requisite four-year service period.

The restricted stock awards and stock options offered directly to Stormpath employees for employment with the Company are deemed replacement awards and a portion of such awards are considered compensation for pre-combination service. Of the $9.1 million total aggregate fair value of the awards, $1.5 million is related to pre-combination service and is recognized as goodwill and a reduction to the post-combination compensation expense. The post-combination expenses for the restricted stock awards and stock options are $5.5 million and $2.1 million, respectively. The expense related to the restricted stock awards will be recognized over two or three years based on an accelerated attribution method. The expense for the stock options will be recognized ratably over the requisite service period.

As of January 31, 2018, there was $2.2 million of unrecognized compensation expense related to unvested restricted stock awards, which is expected to be recognized over the remaining weighted average life of 1.5 years.

As of January 31, 2018, there was $1.6 million of unrecognized compensation cost related to unvested stock options, which is expected to be recognized over the remaining weighted average life of 2.4 years. The related stock options expense and activity are included within the Stock Options section above.

All of these shares are outstanding as of January 31, 2018.

Employee Stock Purchase Plan

In February 2017, the Company’s board of directors adopted, and in March 2017, the Company’s stockholders approved the 2017 Employee Stock Purchase Plan, or the ESPP, which became effective prior to the completion of the IPO. The ESPP initially reserves and authorizes the issuance of up to a total of 3,000,000 shares of Class A common stock to participating employees. Except for the initial offering period, the ESPP provides for 12-month offering periods beginning June 21 and December 21 of each year, and each offering period will consist of two six-month purchase periods. The initial offering period began April 7, 2017 and will end on June 20, 2018.

The Company estimated the fair value of ESPP purchase rights using a Black-Scholes option pricing model with the following assumptions:



	As of January 31, 2018
Expected volatility	32% - 38%
Expected term (in years)	0.5-1.2
Risk-free interest rate	0.95%-1.73%
Expected dividend yield	—

During the year ended January 31, 2018, the Company sold 569,373 shares of its common stock under the ESPP. The shares were purchased at a weighted-average purchase price of $14.70 with proceeds of $8.4 million.

As of January 31, 2018, there was $4.0 million of unrecognized stock-based compensation expense related to the ESPP that is expected to be recognized over an average vesting period of 0.4 years.

Income Taxes

12 Months Ended

Jan. 31, 2018

Income Tax Disclosure [Abstract]

Income Taxes

The domestic and foreign components of pre-tax loss for the years ended January 31, 2018, 2017 and 2016 are as follows (in thousands):



	Year Ended January 31,
	2018			2017			2016
Domestic	$	(117,368	)	$	(84,938	)	$	(76,953	)
Foreign	2,688			1,854			946
Loss before provision for (benefit from) income taxes	$	(114,680	)	$	(83,084	)	$	(76,007	)

The components of the provision for (benefit from) income taxes for the years ended January 31, 2018, 2017 and 2016 are as follows (in thousands):



	Year Ended January 31,
	2018			2017			2016
Current:
Federal	$	—		$	—		$	—
State	—			18			—
Foreign	183			426			295
Total current provision for income taxes	$	183		$	444		$	295
Deferred:
Federal	$	(32	)	$	60		$	60
State	10			6			6
Foreign	(482		)	(85		)	(66		)
Total deferred provision for (benefit from) income taxes	$	(504	)	$	(19	)	$	—
Total provision for (benefit from) income taxes	$	(321	)	$	425		$	295

As a result of the Company’s history of net operating losses and full valuation allowance against its deferred tax assets, the income tax provision was related to foreign taxes and tax amortization of goodwill for the years ended January 31, 2018, 2017 and 2016. For the year ended January 31, 2018, the income tax benefit resulted from $1.3 million of excess tax deductions related to option exercises by foreign employees, a portion of which we intend to use to claim a refund of taxes paid in prior years.

The following is a reconciliation of the statutory federal income tax rate to the Company’s effective tax rate for the years ended January 31, 2018, 2017 and 2016:



	Year Ended January 31,
	2018		2017		2016
Tax at federal statutory rate	33.8	%	34.0	%	34.0	%
State income taxes, net of federal benefit	3.3		3.3		2.7
Change in valuation allowance	(23.5	)	(32.4	)	(33.8	)
Stock-based compensation	39.9		(4.5	)	(3.1	)
Tax Cuts and Jobs Act of 2017	(53.2	)	—		—
Other, net	(0.1	)	(0.9	)	(0.2	)
Effective tax rate	0.2	%	(0.5	)%	(0.4	)%

The tax effects of temporary differences and related deferred tax assets and liabilities as of January 31, 2018 and 2017 are as follows (in thousands):



	As of January 31,
	2018			2017
Deferred tax assets:
Net operating loss carryforwards	$	123,013		$	98,587
Stock-based compensation	7,926			3,611
Deferred revenue	1,391			4,497
Other reserves and accruals	3,084			3,768
Credits	791			625
Total deferred tax assets	136,205			111,088
Valuation allowance	(125,874		)	(98,379		)
Total deferred tax assets, net	10,331			12,709
Deferred tax liabilities:
Deferred commissions	(6,849		)	(8,802		)
Capitalized internal-use software costs	(2,389		)	(2,816		)
Goodwill	(175		)	(196		)
Depreciation and amortization	(441		)	(953		)
Total deferred tax liabilities	(9,854		)	(12,767		)
Net deferred tax assets (liabilities)	$	477		$	(58	)

As a result of continuing losses, the Company has determined that it is not more likely than not that it will realize the benefits of the U.S. deferred tax assets and, therefore, the Company has recorded a valuation allowance to reduce the carrying value of the U.S. deferred tax assets, net of U.S. deferred tax liabilities, to approximately zero. The U.S. valuation allowance increased by $27.5 million and $26.9 million during the years ended January 31, 2018 and 2017, respectively.

As of January 31, 2018 and 2017, the Company had approximately $490.6 million and $264.7 million, respectively, of federal and $295.6 million and $164.2 million, respectively, of state net operating loss carryforwards available to offset future taxable income. If not utilized, the federal and state net operating loss carryforwards will begin to expire in 2029 and 2021, respectively. As of January 31, 2018, the Company had approximately $2.3 million of UK net operating losses which do not expire.

As of January 31, 2018, the Company had federal and California research and development tax credit carryforwards of $6.2 million and $5.6 million, respectively. The federal research and development credits will start to expire in 2030 while the California research and development credits do not expire. The Company has California Enterprise Zone credits of $1 million that begin to expire in 2023.

The Company attributes net revenue, costs and expenses to domestic and foreign components based on the terms of its agreements with its subsidiaries. The Company does not provide for federal income taxes on the undistributed earnings of its foreign subsidiaries as such earnings are to be reinvested offshore indefinitely. If the Company repatriated these earnings, the resulting income tax liability would be insignificant. The Company is subject to taxation in the United States and various states and foreign jurisdictions.

On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (“Tax Act”) was signed into law making significant changes to the Internal Revenue Code. Changes include, but are not limited to, a corporate tax rate decrease to 21% effective for tax years beginning after December 31, 2017. This change in tax rate resulted in a reduction in our net U.S. deferred tax assets before valuation allowance by $61.0 million, which was fully offset by a reduction in our valuation allowance. The Tax Act provided for a one-time deemed mandatory repatriation of post-1986 undistributed foreign subsidiary earnings and profits, or E&P. Our preliminary calculations show that we had negative net undistributed foreign E&P and are not subject to the deemed mandatory repatriation of year end. The other provisions of the Tax Act did not have a material impact on our consolidated financial statements as of January 31, 2018.

In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (SAB 118), which allows us to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. Although the rate reduction is known, the impact of the change is based on estimates of our net U.S. deferred tax assets before valuation allowance as of January 31, 2018. Additionally, potential further guidance may be forthcoming from the Financial Accounting Standards Board and the Securities and Exchange Commission, as well as regulations, interpretations and rulings from federal and state tax agencies, which could result in additional impacts.

The Tax Act contains a number of additional provisions which may impact the Company in future years. However, since the Tax Act was recently finalized and ongoing guidance and accounting interpretation is expected over the next 12 months, the Company has not yet elected any changes to accounting policies and the Company’s analysis is ongoing. Provisional accounting impacts may change in future reporting periods until the accounting analysis is finalized, which will occur no later than one year from the date the Tax Act was enacted.

The Company’s ability to utilize the net operating loss and tax credit carryforwards in the future may be subject to substantial restrictions in the event of past or future ownership changes as defined in Section 382 of the Internal Revenue Code and similar state tax laws.

A reconciliation of beginning and ending amount of unrecognized tax benefit is as follows (in thousands):



	Year Ended January 31,
	2018		2017		2016
Gross amount of unrecognized tax benefits as of the beginning of the year	$	5,775	$	3,512	$	1,889
Additions based on tax positions related to current year	5,944		2,263		1,623
Gross amount of unrecognized tax benefits as of the end of the year	$	11,719	$	5,775	$	3,512

The material jurisdictions in which the Company is subject to potential examination include the United States, California and the United Kingdom. Due to the Company’s net operating loss carryforwards, all tax years since inception remain subject to examination by federal and California taxing authorities. For the United Kingdom, the Company has an open examination for fiscal year 2016, but is no longer subject to examinations for fiscal years prior to 2016.

As of January 31, 2018, 2017 and 2016, the Company had unrecognized tax benefits which would not impact the effective tax rate because of the valuation allowance. The Company’s policy is to include interest and penalties related to unrecognized tax benefits within the provision for income taxes. The Company does not have any uncertain tax positions as of January 31, 2018 for which it is reasonably possible that the positions will increase or decrease within the next twelve months. As of January 31, 2018 and 2017, the Company has not accrued any interest or penalties related to unrecognized tax benefits.

Net Loss Per Share

12 Months Ended

Jan. 31, 2018

Earnings Per Share [Abstract]

Net Loss Per Share

The Company computes net loss per share of common stock in conformity with the two-class method required for participating securities. The Company considers all series of Preferred Stock to be participating securities as the holders of the Preferred Stock are entitled to receive a non-cumulative dividend on a pari passu basis in the event that a dividend is paid on the common stock. The holders of the Preferred Stock do not have a contractual obligation to share in the Company’s losses. As such, the Company’s net losses for the years ended January 31, 2018, 2017 and 2016, were not allocated to these participating securities.

The following table presents the calculation of basic and diluted net loss per share for periods presented (dollars in thousands, except per share data):



	Year Ended January 31,
	2018						2017					2016
	Class A			Class B			Class A		Class B			Class A		Class B

Numerator:
Net loss	$	(33,293	)	$	(81,066	)	$	—	$	(83,509	)	$	—	$	(76,302	)
Denominator:
Weighted-average shares outstanding, basic and diluted	24,165			58,839			—		19,038			—		17,817
Net loss per share attributable to common stockholders, basic and diluted	$	(1.38	)	$	(1.38	)	$	—	$	(4.39	)	$	—	$	(4.28	)

The Company was in a loss position for all periods presented; accordingly, basic net loss per share is the same as diluted net loss per share as the inclusion of all potential common shares outstanding would have been anti-dilutive. Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows (in thousands):



	Year Ended January 31,
	2018	2017	2016

Restricted common stock issued and outstanding	800	—	—
Unvested RSUs issued and outstanding	2,863	—	—
Unvested restricted stock awards issued and outstanding	599	—	—
Shares committed under the ESPP	1,149	—	—
Unvested shares subject to repurchase	188	—	—
Conversion of convertible preferred stock	—	59,465	59,465
Issued and outstanding stock options	24,917	32,866	22,000
Conversion of common stock warrant	—	188	188
Conversion of convertible Series B warrant	—	29	29
	30,516	92,548	81,682

Subsequent Events	12 Months Ended
Subsequent Events	Jan. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On February 22, 2018, the Company priced its private offering of $300.0 million aggregate principal amount of Convertible Senior Notes due 2023 (the “Initial Notes”). On February 23, 2018, the initial purchasers in the offering of the Notes exercised their option to purchase an additional $45.0 million aggregate principal amount of the Notes (the “Additional Notes” and together with the “Initial Notes”, the “Notes”), bringing the total aggregate principal amount of Notes to $345.0 million. On February 27, 2018, the Company received approximately $334.0 million in net proceeds from the offering of the Notes, after deducting the initial purchasers’ discount and commissions and estimated offering expenses payable by the Company. The Company used an aggregate amount of $80.0 million of the net proceeds from the sale of the Notes to purchase the Note Hedge Transactions (as defined below), which was partially offset by proceeds of $52.4 million received from the Warrant Transactions (as defined below). The Notes are senior, unsecured obligations of the Company and bear interest at a rate of 0.25% per year. Interest is payable semi-annually in arrears on February 15 and August 15 of each year, beginning on August 15, 2018. The Notes will mature on February 15, 2023, unless earlier repurchased or converted. The Company may not redeem the Notes prior to their maturity. The Notes are convertible into shares of Company’s Class A common stock at an initial conversion rate of 20.6795 shares of Class A common stock per $1,000 principal amount, which is equal to an initial conversion price of approximately $48.36 per share of Class A common stock, subject to adjustment. Prior to October 15, 2022, the Notes will be convertible at the option of holders during certain periods, upon satisfaction of certain limited conditions. Thereafter, the Notes will be convertible at any time until the close of business on the second scheduled trading day immediately preceding the maturity date. Upon conversion, the Notes may be settled in shares of the Company’s Class A common stock, cash or a combination of cash and shares of the Company’s Class A common stock, at the Company’s election. Holders of the Notes will have the right to require the Company to repurchase all or a portion of their Notes upon the occurrence of a fundamental change (as defined in the indenture governing the Notes) at a purchase price of 100% of their principal amount plus any accrued and unpaid interest. In connection with the pricing of the Notes, the Company entered into convertible note hedge transactions (the "Note Hedge Transactions") with some of the initial purchasers of the Notes and/or their respective affiliates (the "Option Counterparties"). The Note Hedge Transactions are purchased call options containing a strike price equal to the initial conversion price of the Notes and an expiration date commensurate with the maturity date of the Notes. The Note Hedge Transactions are expected generally to reduce the potential dilution to the Class A common stock and/or offset the potential cash payments that the Company could be required to make in excess of the principal amount upon conversion of any Notes. The Company also entered into separate warrant transactions (the "Warrant Transactions") with the Option Counterparties pursuant to which the Company sold warrants for the purchase of the Company’s Class A common stock. These warrants will expire on May 15, 2023. The Warrant Transactions could separately have a dilutive effect to the extent that the market price per share of the Company’s Class A common stock exceeds the strike price of the warrants unless, subject to the terms of the Warrant Transactions, the Company elects to cash settle the warrants. The strike price of the warrants will initially be $68.06 per share, which represents a premium of 90.00% above the closing sale price of the Company’s Class A common stock on February 22, 2018, and is subject to certain adjustments under the terms of the Warrant Transactions.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Jan. 31, 2018

Accounting Policies [Abstract]

Basis of Presentation

The accompanying consolidated financial statements, which include the accounts of the Company and its wholly owned subsidiaries, have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP).

Principles of Consolidation

All intercompany balances and transactions have been eliminated in consolidation. Certain immaterial reclassifications of prior period amounts have been made in our consolidated balance sheets and consolidated statements of cash flows to conform to the current period presentation.

Fiscal Period

The Company’s fiscal year ends on January 31. References to fiscal 2018, for example, refer to the fiscal year ended January 31, 2018.

Use of Estimates

The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates, judgments and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The Company bases its estimates on historical experience and on other assumptions that its management believes are reasonable under the circumstances. Actual results could vary from those estimates. The Company’s most significant estimates and judgments involve revenue recognition with respect to the determination of the relative selling prices for the Company’s services, determination of the fair value of the Company’s common stock prior to the completion of the IPO, valuation of the Company’s stock-based awards, valuation of deferred income tax assets and contingencies.

Foreign Currency

The functional currencies of the Company’s foreign subsidiaries are the respective local currencies. Translation adjustments arising from the use of differing exchange rates from period to period are included in accumulated other comprehensive loss within the consolidated statements of redeemable convertible preferred stock and stockholders’ equity (deficit). Foreign currency transaction gains and losses are included in other expense, net in the consolidated statements of operations and were not material for the years ended January 31, 2018, 2017 or 2016. All assets and liabilities denominated in a foreign currency are translated into U.S. dollars at the exchange rate on the balance sheet date. Revenue and expenses are translated at the average exchange rate during the period, and equity balances are translated using historical exchange rates.

Segment Information

Revenue Recognition

The Company commences revenue recognition when all of the following criteria are met:


•	There is persuasive evidence of an arrangement;


•	Delivery has occurred;


•	The amount of fees to be paid by the customer is fixed or determinable; and


•	Collection of the fees is reasonably assured.

Subscription Revenue

Professional Services Revenue

The Company’s professional services principally consist of customer specific requests for application integrations, user interface enhancements and other customer specific requests.

Multiple Element Arrangements

Deferred Revenue

Deferred Commissions

Cost of Revenue

Cash and Cash Equivalents

Short-term Investments

Accounts Receivable and Allowances

Property and Equipment

The useful lives of property and equipment are as follows:



	Useful lives
Capitalized internal-use software costs	3 years
Computers and equipment	3 years
Furniture and fixtures	7 years
Leasehold improvements	Shorter of 7 years or remaining lease term

Capitalized Internal-Use Software Costs

Business Combinations

Goodwill and Other Long-Lived Assets

The Company amortizes intangible assets with finite lives on a straight-line basis over their estimated useful lives in cost of revenue in the consolidated statements of operations.

Advertising Expenses

Advertising costs are expensed as incurred. Advertising expense was $9.4 million, $4.4 million, and $3.7 million for the years ended January 31, 2018, 2017 and 2016.

Deferred Offering Costs

Stock-Based Compensation

Risk-free rate — The Company uses the U.S. Treasury yield that corresponds with the expected term.

Expected dividend yield — The Company utilizes a dividend yield of zero, as it does not currently issue dividends and does not expect to in the future.

Income Taxes

The Company recognizes and measures tax benefits from uncertain tax positions using a two-step approach.

Facility Leases

Concentrations of Risk and Significant Customers

Net Loss per Share

Recently Adopted and Not Yet Adopted Accounting Pronouncements

The new standard will impact the following policies and disclosures:


•	removal of the current limitation on contingent revenue will result in revenue being recognized earlier for certain contracts;


•	revenue for all professional services will be recognized based on proportional performance;


•	required disclosures including information about the transaction price allocated to remaining performance obligations and related timing of revenue recognition; and


•	accounting for deferred commissions including expanding the costs that qualify for deferral and increasing the amortization period beyond the initial contract to include anticipated renewals.

Select consolidated statement of operations line items, which reflect the adoption of the new standard are as follows (in millions, except per share data):



	Year Ended January 31,
	2018									2017
	As Reported			Adoption of ASU 2014-09			As Adjusted			As Reported			Adoption of ASU 2014-09			As Adjusted
Revenue
Subscription	$	239.2		$	(1.2	)	$	238.0		$	143.1		$	1.9		$	145.0
Professional services and other	20.8			(0.7		)	20.1			17.2			(2.1		)	15.1
Total revenue	260.0			(1.9		)	258.1			160.3			(0.2		)	160.1
Sales and marketing	173.0			(8.0		)	165.0			118.7			(8.0		)	110.8
Total operating expenses	295.6			(8.0		)	287.6			187.5			(8.0		)	179.5
Net loss	(114.4		)	6.1			(108.3		)	(83.5		)	7.8			(75.7		)
Net loss per share, basic and diluted	(1.38		)	0.08			(1.30		)	(4.39		)	0.41			(3.98		)

Select consolidated balance sheet line items, which reflect the adoption of the new standard are as follows (in millions):



	As of January 31, 2018									As of January 31, 2017
	As Reported			Adoption of ASU 2014-09			As Adjusted			As Reported			Adoption of ASU 2014-09			As Adjusted
Assets
Current assets:
Deferred commissions	$	16.5		$	1.3		$	17.8		$	13.5		$	(0.3	)	$	13.2
Prepaid expenses and other current assets	17.0			0.4			17.4			7.0			1.3			8.3
Total current assets	315.4			1.7			317.1			92.8			1.0			93.8
Deferred commissions, noncurrent	11.0			29.8			40.8			10.1			23.4			33.5
Total assets	$	367.4		$	31.5		$	398.9		$	130.6		$	24.4		$	155.0

Liabilities and stockholders’ equity (deficit)
Deferred revenue	$	162.6		$	(3.3	)	$	159.3		$	108.0		$	(3.9	)	$	104.1
Total current liabilities	190.8			(3.3		)	187.5			134.5			(3.9		)	130.6
Deferred revenue, noncurrent	6.0			(0.7		)	5.3			5.7			(1.0		)	4.7
Total liabilities	203.8			(4.0		)	199.8			146.3			(5.0		)	141.3
Accumulated deficit	(402.5		)	35.5			(367.0		)	(287.9		)	29.4			(258.5		)
Total stockholders’ equity (deficit)	$	163.6		$	35.5		$	199.1		$	(243.6	)	$	29.4		$	(214.2	)

Recent Accounting Pronouncements Not Yet Adopted

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Jan. 31, 2018

Accounting Policies [Abstract]

Schedule of Property Plant and Equipment Estimated Useful Life

The useful lives of property and equipment are as follows:



	Useful lives
Capitalized internal-use software costs	3 years
Computers and equipment	3 years
Furniture and fixtures	7 years
Leasehold improvements	Shorter of 7 years or remaining lease term

Property and equipment consisted of the following (in thousands):



	As of January 31,
	2018			2017

Computers and equipment	$	5,384		$	3,753
Furniture and fixtures	7,083			4,204
Leasehold improvements	8,188			7,175
Property and equipment, gross	20,655			15,132
Less accumulated depreciation	(8,115		)	(4,106		)
Property and equipment, net	$	12,540		$	11,026

Schedule of Revenue by Geographic Area

The following table sets forth revenue by geographic area (in thousands):



	Year Ended January 31,
	2018		2017		2016

United States	$	220,382	$	138,925	$	75,583
International	39,608		21,401		10,324
Total	$	259,990	$	160,326	$	85,907

Schedule of Impact of New Accounting Pronouncements

Select consolidated statement of operations line items, which reflect the adoption of the new standard are as follows (in millions, except per share data):



	Year Ended January 31,
	2018									2017
	As Reported			Adoption of ASU 2014-09			As Adjusted			As Reported			Adoption of ASU 2014-09			As Adjusted
Revenue
Subscription	$	239.2		$	(1.2	)	$	238.0		$	143.1		$	1.9		$	145.0
Professional services and other	20.8			(0.7		)	20.1			17.2			(2.1		)	15.1
Total revenue	260.0			(1.9		)	258.1			160.3			(0.2		)	160.1
Sales and marketing	173.0			(8.0		)	165.0			118.7			(8.0		)	110.8
Total operating expenses	295.6			(8.0		)	287.6			187.5			(8.0		)	179.5
Net loss	(114.4		)	6.1			(108.3		)	(83.5		)	7.8			(75.7		)
Net loss per share, basic and diluted	(1.38		)	0.08			(1.30		)	(4.39		)	0.41			(3.98		)

Select consolidated balance sheet line items, which reflect the adoption of the new standard are as follows (in millions):



	As of January 31, 2018									As of January 31, 2017
	As Reported			Adoption of ASU 2014-09			As Adjusted			As Reported			Adoption of ASU 2014-09			As Adjusted
Assets
Current assets:
Deferred commissions	$	16.5		$	1.3		$	17.8		$	13.5		$	(0.3	)	$	13.2
Prepaid expenses and other current assets	17.0			0.4			17.4			7.0			1.3			8.3
Total current assets	315.4			1.7			317.1			92.8			1.0			93.8
Deferred commissions, noncurrent	11.0			29.8			40.8			10.1			23.4			33.5
Total assets	$	367.4		$	31.5		$	398.9		$	130.6		$	24.4		$	155.0

Liabilities and stockholders’ equity (deficit)
Deferred revenue	$	162.6		$	(3.3	)	$	159.3		$	108.0		$	(3.9	)	$	104.1
Total current liabilities	190.8			(3.3		)	187.5			134.5			(3.9		)	130.6
Deferred revenue, noncurrent	6.0			(0.7		)	5.3			5.7			(1.0		)	4.7
Total liabilities	203.8			(4.0		)	199.8			146.3			(5.0		)	141.3
Accumulated deficit	(402.5		)	35.5			(367.0		)	(287.9		)	29.4			(258.5		)
Total stockholders’ equity (deficit)	$	163.6		$	35.5		$	199.1		$	(243.6	)	$	29.4		$	(214.2	)

Cash Equivalents and Short-term Investments (Tables)

12 Months Ended

Jan. 31, 2018

Investments, Debt and Equity Securities [Abstract]

Schedule of Amortized Costs, Unrealized Gains and Losses and Estimated Fair Value of Cash Equivalents and Short-term Investments



	As of January 31, 2018
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash equivalents:
Money market funds	$	90,770	$	—	$	—		$	90,770
Total cash equivalents	$	90,770	$	—	$	—		$	90,770
Short-term investments:
Commercial paper	$	15,946	$	—	$	—		$	15,946
U.S. treasury securities	61,896		—		(158		)	61,738
Corporate debt securities	24,125		—		(44		)	24,081
Total short-term investments	101,967		—		(202		)	101,765
Total	$	192,737	$	—	$	(202	)	$	192,535



	As of January 31, 2017
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash equivalents:
Money market funds	$	10,565	$	—	$	—		$	10,565
Total cash equivalents	$	10,565	$	—	$	—		$	10,565
Short-term investments:
Asset-backed securities	$	1,538	$	—	$	—		$	1,538
Corporate debt securities	12,842		13		(3		)	12,852
Total short-term investments	14,380		13		(3		)	14,390
Total	$	24,945	$	13	$	(3	)	$	24,955

Schedule of Contractual Maturities of Short-term Investments

The following tables present the contractual maturities of the Company’s short-term investments as of January 31, 2018 and 2017 (in thousands):



	As of January 31, 2018				As of January 31, 2017
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due within one year	$	93,421	$	93,237	$	12,842	$	12,852
Due between one to five years	8,546		8,528		1,538		1,538
	$	101,967	$	101,765	$	14,380	$	14,390

Fair Value Measurements (Tables)

12 Months Ended

Jan. 31, 2018

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table presents information about the Company’s financial assets that are measured at fair value on a recurring basis using the above input categories (in thousands):



	As of January 31, 2018
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	90,770	$	—	$	—	$	90,770
Total cash equivalents	$	90,770	$	—	$	—	$	90,770
Short-term investments:
Commercial paper	$	—	$	15,946	$	—	$	15,946
U.S. treasury securities	—		61,738		—		61,738
Corporate debt securities	—		24,081		—		24,081
Total short-term investments	—		101,765		—		101,765
Total cash equivalents and short-term investments	$	90,770	$	101,765	$	—	$	192,535



	As of January 31, 2017
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	10,565	$	—	$	—	$	10,565
Total cash equivalents	$	10,565	$	—	$	—	$	10,565
Short-term investments:
Asset-backed securities	$	—	$	1,538	$	—	$	1,538
Corporate debt securities	—		12,852		—		12,852
Total short-term investments	—		14,390		—		14,390
Total cash equivalents and short-term investments	$	10,565	$	14,390	$	—	$	24,955
Liabilities:
Series B redeemable convertible preferred stock warrant	$	—	$	—	$	304	$	304

Schedule of Changes in Series B Redeemable Convertible Preferred Stock Warrant Fair Value

The change in the fair value of the Series B redeemable convertible preferred stock warrant was as follows (in thousands):



Balance at January 31, 2016	$	237
Increase in fair value of warrant	67
Balance at January 31, 2017	304
Increase in fair value of warrant	104
Reclassification of remaining warrant liability to additional paid-in capital	(408		)
Balance at January 31, 2018	$	—

Goodwill and Intangible Assets, net (Tables)

12 Months Ended

Jan. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

Goodwill balances as of January 31, 2018 and 2017 were as follows (in thousands):




Balance as of January 31, 2017	$	2,630
Goodwill recorded in connection with Stormpath acquisition	3,652
Balance as of January 31, 2018	$	6,282

Schedule of Intangible Assets, net

Intangible assets consisted of the following (in thousands):



	As of January 31, 2018
	Gross		Accumulated Amortization			Write-offs			Net
Capitalized internal-use software costs	$	17,511	$	(5,172	)	$	(1,077	)	$	11,262
Software licenses	1,094		(558		)	(37		)	499
Purchased developed technology	570		(570		)	—			—
	$	19,175	$	(6,300	)	$	(1,114	)	$	11,761



	As of January 31, 2017
	Gross		Accumulated Amortization			Write-offs		Net
Capitalized internal-use software costs	$	10,859	$	(2,487	)	$	—	$	8,372
Software licenses	1,093		(314		)	—		779
Purchased developed technology	570		(566		)	—		4
	$	12,522	$	(3,367	)	$	—	$	9,155

Schedule of Estimated Remaining Amortization Expense for Intangible Assets

As of January 31, 2018, estimated remaining amortization expense for the intangible assets by fiscal year is as follows (in thousands):



2019	$	2,954
2020	1,943
2021	6,864
Total	$	11,761

Balance Sheet Components (Tables)

12 Months Ended

Jan. 31, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Property and Equipment, net

The useful lives of property and equipment are as follows:



	Useful lives
Capitalized internal-use software costs	3 years
Computers and equipment	3 years
Furniture and fixtures	7 years
Leasehold improvements	Shorter of 7 years or remaining lease term

Property and equipment consisted of the following (in thousands):



	As of January 31,
	2018			2017

Computers and equipment	$	5,384		$	3,753
Furniture and fixtures	7,083			4,204
Leasehold improvements	8,188			7,175
Property and equipment, gross	20,655			15,132
Less accumulated depreciation	(8,115		)	(4,106		)
Property and equipment, net	$	12,540		$	11,026

Schedule of Allowances

The Company’s allowances for the years ended January 31, 2018, 2017 and 2016 are as follows (in thousands):



	As of January 31,
	2018			2017			2016

Balance, beginning of period	$	1,306		$	861		$	117
Additions	431			1,185			979
Write-offs	(265		)	(740		)	(235		)
Balance, end of period	$	1,472		$	1,306		$	861

Schedule of Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):



	As of January 31,
	2018		2017

Deposit related to early exercise of unvested options	$	1,119	$	2,168
Accrued expenses	3,389		4,297
Redeemable convertible preferred stock warrant liability	—		304
Accrued taxes payable	835		826
Deferred rent, current	520		225
Other	324		543
Accrued expenses and other current liabilities	$	6,187	$	8,363

Schedule of Other Liabilities, noncurrent

Other liabilities, noncurrent consisted of the following (in thousands):



	As of January 31,
	2018		2017

Deferred rent, noncurrent	$	5,010	$	4,615
Deferred tax liabilities	175		132
Other	1,832		1,332
Other liabilities, noncurrent	$	7,017	$	6,079

Commitments and Contingencies (Tables)

12 Months Ended

Jan. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Rental Payments for Operating Leases



	Operating Leases		Purchase Obligations		Total
2019	$	14,105	$	13,048	$	27,153
2020	18,243		13,077		31,320
2021	24,719		4,347		29,066
2022	26,521		—		26,521
2023	26,487		—		26,487
Thereafter	144,386		—		144,386
Total contractual obligations	$	254,461	$	30,472	$	284,933

Schedule of Purchase Obligations Fiscal Maturity Schedule



	Operating Leases		Purchase Obligations		Total
2019	$	14,105	$	13,048	$	27,153
2020	18,243		13,077		31,320
2021	24,719		4,347		29,066
2022	26,521		—		26,521
2023	26,487		—		26,487
Thereafter	144,386		—		144,386
Total contractual obligations	$	254,461	$	30,472	$	284,933

Common Stock and Stockholders' Equity (Deficit) (Tables)

12 Months Ended

Jan. 31, 2018

Equity [Abstract]

Schedule of Redeemable Convertible Preferred Stock

The authorized, issued and outstanding shares of redeemable convertible preferred stock (Preferred Stock) and liquidation preferences as of January 31, 2017 were as follows:



Series	Authorized Shares	Issued and Outstanding Shares	Liquidation Preference		Carrying Value
Series A	14,210,789	14,210,783	$	11,373,000	$	11,322,000
Series B	12,015,123	11,986,055	16,500,000		16,420,000
Series C	10,708,782	10,708,780	25,000,000		24,872,000
Series D	6,833,654	6,833,651	27,500,000		27,416,000
Series E	9,484,234	9,484,234	75,000,000		74,500,000
Series F	6,242,000	6,241,936	75,000,000		73,424,000
	59,494,582	59,465,439	$	230,373,000	$	227,954,000

Schedule of Common Stock Reserved for Future Issuance

As of January 31, 2018, shares of common stock reserved for future issuance are as follows:




Options and unvested RSUs outstanding	27,779,974
Available for future stock option and RSU grants	9,842,925
Available for ESPP	2,430,627
	40,053,526

Employee Incentive Plans (Tables)

12 Months Ended

Jan. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Stock-based Compensation Expense by Award Type

Stock-based compensation expense by award type was as follows (in thousands):



	Year Ended January 31,
	2018		2017		2016
Stock options	$	24,186	$	17,127	$	9,832
RSUs	9,104		—		—
ESPP	7,111		—		—
Restricted stock awards	3,281		—		—
Restricted common stock	6,178		—		—
Total	$	49,860	$	17,127	$	9,832

Schedule of Stock-based Compensation Expense by Statement of Operations Location

Stock-based compensation expense was recorded in the following cost and expense categories in the Company’s consolidated statements of operations (in thousands):



	Year Ended January 31,
	2018		2017		2016
Cost of revenue:
Subscription	$	4,600	$	1,979	$	909
Professional services and other	3,137		1,283		553
Research and development	18,107		2,992		1,748
Sales and marketing	13,242		6,029		2,853
General and administrative	10,774		4,844		3,769
Total	$	49,860	$	17,127	$	9,832

Schedule of Stock Option Activity

A summary of the Company’s stock option activity and related information is as follows:



	Number of Options		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding as of January 31, 2017	32,866,862		$	6.01	8.2	$	145,570
Granted	2,676,667		11.56
Exercised	(9,180,242	)	3.66
Canceled	(1,446,242	)	7.76
Outstanding as of January 31, 2018	24,917,045		$	7.37	7.6	$	550,173
As of January 31, 2018:
Vested and expected to vest	24,917,045		$	7.37	7.6	$	550,173
Vested and exercisable	10,205,493		$	5.33	6.9	$	246,189

Schedule of Black-Scholes Option Pricing Model Estimated Fair Value Assumptions

The Company used the Black-Scholes option pricing model to estimate the fair value of stock options granted with the following assumptions:



	Year Ended January 31,
	2018	2017	2016
Expected volatility	40% - 41%	40% - 44%	42% - 46%
Expected term (in years)	6.3 - 6.4	5.5 - 6.9	5.0 - 6.1
Risk-free interest rate	1.87% - 2.21%	1.13% - 2.28%	1.43% - 1.88%
Expected dividend yield	—	—	—

Schedule of Nonvested Restricted Stock Units Activity

A summary of the Company’s RSU activities and related information is as follows:



	Number of RSUs		Weighted- Average Grant Date Fair Value Per Share
Outstanding as of January 31, 2017	—		$	—
Granted	3,012,111		24.37
Vested	—		—
Forfeited	(149,182	)	24.15
Outstanding as of January 31, 2018	2,862,929		$	24.38

Schedule of ESPP Black-Scholes Option Pricing Model Estimated Fair Value Assumptions

The Company estimated the fair value of ESPP purchase rights using a Black-Scholes option pricing model with the following assumptions:



	As of January 31, 2018
Expected volatility	32% - 38%
Expected term (in years)	0.5-1.2
Risk-free interest rate	0.95%-1.73%
Expected dividend yield	—

Income Taxes (Tables)

12 Months Ended

Jan. 31, 2018

Income Tax Disclosure [Abstract]

Schedule of Domestic and Foreign Components of Pre-tax Loss

The domestic and foreign components of pre-tax loss for the years ended January 31, 2018, 2017 and 2016 are as follows (in thousands):



	Year Ended January 31,
	2018			2017			2016
Domestic	$	(117,368	)	$	(84,938	)	$	(76,953	)
Foreign	2,688			1,854			946
Loss before provision for (benefit from) income taxes	$	(114,680	)	$	(83,084	)	$	(76,007	)

Schedule of Components of Provision for (Benefit from) Income Taxes

The components of the provision for (benefit from) income taxes for the years ended January 31, 2018, 2017 and 2016 are as follows (in thousands):



	Year Ended January 31,
	2018			2017			2016
Current:
Federal	$	—		$	—		$	—
State	—			18			—
Foreign	183			426			295
Total current provision for income taxes	$	183		$	444		$	295
Deferred:
Federal	$	(32	)	$	60		$	60
State	10			6			6
Foreign	(482		)	(85		)	(66		)
Total deferred provision for (benefit from) income taxes	$	(504	)	$	(19	)	$	—
Total provision for (benefit from) income taxes	$	(321	)	$	425		$	295

Schedule of Effective Income Tax Rate Reconciliation

The following is a reconciliation of the statutory federal income tax rate to the Company’s effective tax rate for the years ended January 31, 2018, 2017 and 2016:



	Year Ended January 31,
	2018		2017		2016
Tax at federal statutory rate	33.8	%	34.0	%	34.0	%
State income taxes, net of federal benefit	3.3		3.3		2.7
Change in valuation allowance	(23.5	)	(32.4	)	(33.8	)
Stock-based compensation	39.9		(4.5	)	(3.1	)
Tax Cuts and Jobs Act of 2017	(53.2	)	—		—
Other, net	(0.1	)	(0.9	)	(0.2	)
Effective tax rate	0.2	%	(0.5	)%	(0.4	)%

Schedule of Deferred Tax Assets and Liabilities

The tax effects of temporary differences and related deferred tax assets and liabilities as of January 31, 2018 and 2017 are as follows (in thousands):



	As of January 31,
	2018			2017
Deferred tax assets:
Net operating loss carryforwards	$	123,013		$	98,587
Stock-based compensation	7,926			3,611
Deferred revenue	1,391			4,497
Other reserves and accruals	3,084			3,768
Credits	791			625
Total deferred tax assets	136,205			111,088
Valuation allowance	(125,874		)	(98,379		)
Total deferred tax assets, net	10,331			12,709
Deferred tax liabilities:
Deferred commissions	(6,849		)	(8,802		)
Capitalized internal-use software costs	(2,389		)	(2,816		)
Goodwill	(175		)	(196		)
Depreciation and amortization	(441		)	(953		)
Total deferred tax liabilities	(9,854		)	(12,767		)
Net deferred tax assets (liabilities)	$	477		$	(58	)

Schedule of Unrecognized Tax Benefits Roll Forward

A reconciliation of beginning and ending amount of unrecognized tax benefit is as follows (in thousands):



	Year Ended January 31,
	2018		2017		2016
Gross amount of unrecognized tax benefits as of the beginning of the year	$	5,775	$	3,512	$	1,889
Additions based on tax positions related to current year	5,944		2,263		1,623
Gross amount of unrecognized tax benefits as of the end of the year	$	11,719	$	5,775	$	3,512

Net Loss Per Share (Tables)

12 Months Ended

Jan. 31, 2018

Earnings Per Share [Abstract]

Schedule of Basic and Diluted Net Loss Per Share

The following table presents the calculation of basic and diluted net loss per share for periods presented (dollars in thousands, except per share data):



	Year Ended January 31,
	2018						2017					2016
	Class A			Class B			Class A		Class B			Class A		Class B

Numerator:
Net loss	$	(33,293	)	$	(81,066	)	$	—	$	(83,509	)	$	—	$	(76,302	)
Denominator:
Weighted-average shares outstanding, basic and diluted	24,165			58,839			—		19,038			—		17,817
Net loss per share attributable to common stockholders, basic and diluted	$	(1.38	)	$	(1.38	)	$	—	$	(4.39	)	$	—	$	(4.28	)

Schedule of Potentially Dilutive Securities Excluded from Computation of Diluted Per Share

Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows (in thousands):



	Year Ended January 31,
	2018	2017	2016

Restricted common stock issued and outstanding	800	—	—
Unvested RSUs issued and outstanding	2,863	—	—
Unvested restricted stock awards issued and outstanding	599	—	—
Shares committed under the ESPP	1,149	—	—
Unvested shares subject to repurchase	188	—	—
Conversion of convertible preferred stock	—	59,465	59,465
Issued and outstanding stock options	24,917	32,866	22,000
Conversion of common stock warrant	—	188	188
Conversion of convertible Series B warrant	—	29	29
	30,516	92,548	81,682

Overview and Basis of Presentation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Apr. 07, 2017	Apr. 06, 2017	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Class of Stock [Line Items]
Initial public offering costs			$ 4,038	$ 1,584	$ 0
Class A Common Stock
Class of Stock [Line Items]
Price per share in initial public offering (in dollars per share)	$ 17.00
Common stock outstanding (in shares)			70,609,898	0
Redeemable Convertible Preferred Stock
Class of Stock [Line Items]
Redeemable convertible preferred stock converted to common class B stock (in shares)		59,491,640
Class B Common Stock
Class of Stock [Line Items]
Common class B stock after conversion of redeemable convertible stock (in shares)		59,491,640
Common stock outstanding (in shares)			33,361,106	20,229,000
Initial Public Offering
Class of Stock [Line Items]
Proceeds from initial public offering, net of underwriters' discounts and commissions	$ 200,000
Initial public offering costs	$ 5,600
Initial Public Offering \| Class A Common Stock
Class of Stock [Line Items]
Shares issued in initial public offering (in shares)	12,650,000
Underwriters' Option to Purchase Additional Shares \| Class A Common Stock
Class of Stock [Line Items]
Shares issued in initial public offering (in shares)	1,650,000

Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Payment terms for deferred revenue	30 days
Payment terms for deferred commissions	3 months
Advertising expenses	$ 9,400,000	$ 4,400,000	$ 3,700,000
Deferred offering costs	0	3,700,000
Cumulative impact adjustment		0
Goodwill impairments	$ 0	0	$ 0
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative impact adjustment		200,000
Retained Earnings \| Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative impact adjustment		$ 200,000
ESPP
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Expected dividend yield	0.00%
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue recognition, customer contract period	1 year
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue recognition, customer contract period	3 years
Capitalized internal-use software costs
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Intangible asset, useful life	3 years
Pro Forma \| Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred incremental commission costs, amortization period	5 years

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives (Details)	12 Months Ended
	Jan. 31, 2018
Capitalized internal-use software costs
Property, Plant and Equipment [Line Items]
Intangible asset, useful life	3 years
Computers and Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	7 years
Leasehold Improvements \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	7 years

Summary of Significant Accounting Policies - Schedule of Revenue by Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 259,990	$ 160,326	$ 85,907
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	220,382	138,925	75,583
International
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 39,608	$ 21,401	$ 10,324

Summary of Significant Accounting Policies - Schedule of Impact of New Accounting Pronouncements (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Revenue
Subscription	$ 239,177	$ 143,136	$ 76,443
Professional services and other	20,813	17,190	9,464
Total revenue	259,990	160,326	85,907
Sales and marketing	172,973	118,742	77,915
Total operating expenses	295,597	187,500	125,871
Net loss	$ (114,359)	$ (83,509)	$ (76,302)
Net loss per share, basic and diluted (in dollars per share)	$ (1.38)	$ (4.39)	$ (4.28)
Current assets:
Deferred commissions	$ 16,481	$ 13,549
Prepaid expenses and other current assets	16,973	7,025
Total current assets	315,416	92,790
Deferred commissions, noncurrent	10,971	10,050
Total assets	367,397	130,635
Liabilities and stockholders’ equity (deficit)
Deferred revenue	162,633	108,012
Total current liabilities	190,760	134,496
Deferred revenue, noncurrent	6,034	5,711
Total liabilities	203,811	146,286
Accumulated deficit	(402,468)	(287,909)
Total stockholders’ equity (deficit)	163,586	(243,605)	$ (181,062)	$ (117,198)
Accounting Standards Update 2014-09 \| Pro Forma
Revenue
Subscription	238,000	145,000
Professional services and other	20,100	15,100
Total revenue	258,100	160,100
Sales and marketing	165,000	110,800
Total operating expenses	287,600	179,500
Net loss	$ (108,300)	$ (75,700)
Net loss per share, basic and diluted (in dollars per share)	$ (1.30)	$ (3.98)
Current assets:
Deferred commissions	$ 17,800	$ 13,200
Prepaid expenses and other current assets	17,400	8,300
Total current assets	317,100	93,800
Deferred commissions, noncurrent	40,800	33,500
Total assets	398,900	155,000
Liabilities and stockholders’ equity (deficit)
Deferred revenue	159,300	104,100
Total current liabilities	187,500	130,600
Deferred revenue, noncurrent	5,300	4,700
Total liabilities	199,800	141,300
Accumulated deficit	(367,000)	(258,500)
Total stockholders’ equity (deficit)	199,100	(214,200)
Difference between Revenue Guidance in Effect before and after Topic 606 \| Accounting Standards Update 2014-09 \| Pro Forma
Revenue
Subscription	(1,200)	1,900
Professional services and other	(700)	(2,100)
Total revenue	(1,900)	(200)
Sales and marketing	(8,000)	(8,000)
Total operating expenses	(8,000)	(8,000)
Net loss	$ 6,100	$ 7,800
Net loss per share, basic and diluted (in dollars per share)	$ 0.08	$ 0.41
Current assets:
Deferred commissions	$ 1,300	$ (300)
Prepaid expenses and other current assets	400	1,300
Total current assets	1,700	1,000
Deferred commissions, noncurrent	29,800	23,400
Total assets	31,500	24,400
Liabilities and stockholders’ equity (deficit)
Deferred revenue	(3,300)	(3,900)
Total current liabilities	(3,300)	(3,900)
Deferred revenue, noncurrent	(700)	(1,000)
Total liabilities	(4,000)	(5,000)
Accumulated deficit	35,500	29,400
Total stockholders’ equity (deficit)	$ 35,500	$ 29,400

Acquisition - Narrative (Details) - Stormpath Inc. $ in Millions	Feb. 17, 2017 USD ($) shares
Business Acquisition [Line Items]
Total purchase price	$ 3.7
Shares included in total consideration (in shares) \| shares	200,000
Restricted common stock
Business Acquisition [Line Items]
Incremental shares issued (in shares) \| shares	800,000
Incremental shares issued	$ 8.6
Stock-based compensation vesting period	2 years
Stormpath Investors
Business Acquisition [Line Items]
Total purchase price	$ 2.2
Stormpath Workforce
Business Acquisition [Line Items]
Total purchase price	1.5
Incremental shares issued	$ 9.1

Cash Equivalents and Short-term Investments - Schedule of Amortized Costs, Unrealized Gains and Losses and Estimated Fair Value of Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Cash equivalents:
Cash equivalents, amortized cost	$ 90,770	$ 10,565
Cash equivalents, estimated fair value	90,770	10,565
Short-term investments:
Investments, amortized cost	101,967	14,380
Investments, estimated fair value	101,765	14,390
Total short-term investments, amortized cost	101,967	14,380
Total short-term investments, unrealized gain	0	13
Total short-term investments, unrealized loss	(202)	(3)
Total short-term investments, estimated fair value	101,765	14,390
Amortized cost	192,737	24,945
Estimated fair value	192,535	24,955
Commercial paper
Short-term investments:
Investments, amortized cost	15,946
Investments, unrealized gain	0
Investments, unrealized loss	0
Investments, estimated fair value	15,946
U.S. treasury securities
Short-term investments:
Investments, amortized cost	61,896
Investments, unrealized gain	0
Investments, unrealized loss	(158)
Investments, estimated fair value	61,738
Asset-backed securities
Short-term investments:
Investments, amortized cost		1,538
Investments, unrealized gain		0
Investments, unrealized loss		0
Investments, estimated fair value		1,538
Corporate debt securities
Short-term investments:
Investments, amortized cost	24,125	12,842
Investments, unrealized gain	0	13
Investments, unrealized loss	(44)	(3)
Investments, estimated fair value	24,081	$ 12,852
Money market funds
Cash equivalents:
Cash equivalents, amortized cost	90,770
Cash equivalents, estimated fair value	$ 90,770

Cash Equivalents and Short-term Investments - Schedule of Contractual Maturities of Short-term Investments (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Amortized Cost
Amortized cost, due within one year	$ 93,421	$ 12,842
Amortized cost, due between one to five years	8,546	1,538
Investments, amortized cost	101,967	14,380
Estimated Fair Value
Estimated fair value, due within one year	93,237	12,852
Estimated fair value, due between one to five years	8,528	1,538
Estimated fair value total	$ 101,765	$ 14,390

Cash Equivalents and Short-term Investments - Narrative (Details)	12 Months Ended
	Jan. 31, 2018 USD ($) investment	Jan. 31, 2017 USD ($) investment	Jan. 31, 2016 USD ($)
Investments, Debt and Equity Securities [Abstract]
Number of short-term investments in unrealized loss positions \| investment	23	5
Gross unrealized gains or losses from available-for-sale securities	$ 0	$ 0	$ 0
Realized gains or losses reclassified out of accumulated other comprehensive income	0	0	$ 0
Other-than-temporary impairment short term investment	$ 0	$ 0

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Assets:
Cash equivalents, fair value	$ 90,770	$ 10,565
Money market funds
Assets:
Cash equivalents, fair value	90,770
Fair Value, Measurements, Recurring
Assets:
Cash equivalents, fair value	90,770	10,565
Short term investments, fair value	101,765	14,390
Total cash equivalents and short-term investments	192,535	24,955
Liabilities:
Series B redeemable convertible preferred stock warrant		304
Fair Value, Measurements, Recurring \| Level 1
Assets:
Cash equivalents, fair value	90,770	10,565
Short term investments, fair value	0	0
Total cash equivalents and short-term investments	90,770	10,565
Liabilities:
Series B redeemable convertible preferred stock warrant		0
Fair Value, Measurements, Recurring \| Level 2
Assets:
Cash equivalents, fair value	0	0
Short term investments, fair value	101,765	14,390
Total cash equivalents and short-term investments	101,765	14,390
Liabilities:
Series B redeemable convertible preferred stock warrant		0
Fair Value, Measurements, Recurring \| Level 3
Assets:
Cash equivalents, fair value	0	0
Short term investments, fair value	0	0
Total cash equivalents and short-term investments	0	0
Liabilities:
Series B redeemable convertible preferred stock warrant		304
Fair Value, Measurements, Recurring \| Commercial paper
Assets:
Short term investments, fair value	15,946
Fair Value, Measurements, Recurring \| Commercial paper \| Level 1
Assets:
Short term investments, fair value	0
Fair Value, Measurements, Recurring \| Commercial paper \| Level 2
Assets:
Short term investments, fair value	15,946
Fair Value, Measurements, Recurring \| Commercial paper \| Level 3
Assets:
Short term investments, fair value	0
Fair Value, Measurements, Recurring \| U.S. treasury securities
Assets:
Short term investments, fair value	61,738
Fair Value, Measurements, Recurring \| U.S. treasury securities \| Level 1
Assets:
Short term investments, fair value	0
Fair Value, Measurements, Recurring \| U.S. treasury securities \| Level 2
Assets:
Short term investments, fair value	61,738
Fair Value, Measurements, Recurring \| U.S. treasury securities \| Level 3
Assets:
Short term investments, fair value	0
Fair Value, Measurements, Recurring \| Asset-backed securities
Assets:
Short term investments, fair value		1,538
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 1
Assets:
Short term investments, fair value		0
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 2
Assets:
Short term investments, fair value		1,538
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 3
Assets:
Short term investments, fair value		0
Fair Value, Measurements, Recurring \| Corporate debt securities
Assets:
Short term investments, fair value	24,081	12,852
Fair Value, Measurements, Recurring \| Corporate debt securities \| Level 1
Assets:
Short term investments, fair value	0	0
Fair Value, Measurements, Recurring \| Corporate debt securities \| Level 2
Assets:
Short term investments, fair value	24,081	12,852
Fair Value, Measurements, Recurring \| Corporate debt securities \| Level 3
Assets:
Short term investments, fair value	0	0
Fair Value, Measurements, Recurring \| Money market funds
Assets:
Cash equivalents, fair value	90,770	10,565
Fair Value, Measurements, Recurring \| Money market funds \| Level 1
Assets:
Cash equivalents, fair value	90,770	10,565
Fair Value, Measurements, Recurring \| Money market funds \| Level 2
Assets:
Cash equivalents, fair value	0	0
Fair Value, Measurements, Recurring \| Money market funds \| Level 3
Assets:
Cash equivalents, fair value	$ 0	$ 0

Fair Value Measurements - Schedule of Changes in Series B Redeemable Convertible Preferred Stock Warrant Fair Value (Details) - Redeemable Convertible Preferred Stock Warrant - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of beginning of period	$ 304	$ 237
Increase in fair value of warrant	104	67
Reclassification of remaining warrant liability to additional paid-in capital	(408)
Balance as of end of period	$ 0	$ 304

Goodwill and Intangible Assets, net - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Apr. 30, 2017	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Goodwill [Line Items]
Goodwill recorded in connection with Stormpath acquisition		$ 3,652,000
Goodwill impairments		0	$ 0	$ 0
Amortization expense		2,900,000	1,800,000	900,000
Reversal of previously capitalized costs		1,114,000	0	0
Stormpath Inc.
Goodwill [Line Items]
Goodwill recorded in connection with Stormpath acquisition	$ 3,652,000
Capitalized internal-use software costs
Goodwill [Line Items]
Acquired intangibles		6,700,000	6,100,000
Stock-based compensation included in capitalized software costs		1,200,000	600,000
Amortization expense		2,700,000	1,600,000	$ 700,000
Reversal of previously capitalized costs		1,077,000	0
Software licenses
Goodwill [Line Items]
Acquired intangibles		0	400,000
Reversal of previously capitalized costs		$ 37,000	$ 0

Goodwill and Intangible Assets, net - Schedule of Goodwill (Details) $ in Thousands	12 Months Ended
	Jan. 31, 2018 USD ($)
Goodwill [Roll Forward]
Balance as of January 31, 2017	$ 2,630
Goodwill recorded in connection with Stormpath acquisition	3,652
Balance as of January 31, 2018	$ 6,282

Goodwill and Intangible Assets, net - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross	$ 19,175	$ 12,522
Accumulated Amortization	(6,300)	(3,367)
Write-offs	(1,114)	0	$ 0
Net	11,761	9,155
Capitalized internal-use software costs
Finite-Lived Intangible Assets [Line Items]
Gross	17,511	10,859
Accumulated Amortization	(5,172)	(2,487)
Write-offs	(1,077)	0
Net	11,262	8,372
Software licenses
Finite-Lived Intangible Assets [Line Items]
Gross	1,094	1,093
Accumulated Amortization	(558)	(314)
Write-offs	(37)	0
Net	499	779
Purchased developed technology
Finite-Lived Intangible Assets [Line Items]
Gross	570	570
Accumulated Amortization	(570)	(566)
Write-offs	0	0
Net	$ 0	$ 4

Goodwill and Intangible Assets, net - Remaining Amortization Expense (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
2019	$ 2,954
2020	1,943
2021	6,864
Total	$ 11,761	$ 9,155

Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,655	$ 15,132
Less accumulated depreciation	(8,115)	(4,106)
Property and equipment, net	12,540	11,026
Depreciation expense	4,000	2,400	$ 1,100
Computers and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,384	3,753
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,083	4,204
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 8,188	$ 7,175

Balance Sheet Components - Schedule of Allowances (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	$ 1,306	$ 861	$ 117
Additions	431	1,185	979
Write-offs	(265)	(740)	(235)
Balance, end of period	$ 1,472	$ 1,306	$ 861

Balance Sheet Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deposit related to early exercise of unvested options	$ 1,119	$ 2,168
Accrued expenses	3,389	4,297
Redeemable convertible preferred stock warrant liability	0	304
Accrued taxes payable	835	826
Deferred rent, current	520	225
Other	324	543
Accrued expenses and other current liabilities	$ 6,187	$ 8,363

Balance Sheet Components - Schedule of Other Liabilities, Noncurrent (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deferred rent, noncurrent	$ 5,010	$ 4,615
Deferred tax liabilities	175	132
Other	1,832	1,332
Other liabilities, noncurrent	$ 7,017	$ 6,079

Debt - Narrative (Details) - Loan and Security Agreement - USD ($)		1 Months Ended	12 Months Ended
	Jun. 17, 2015	Mar. 31, 2017	Jan. 31, 2018	Nov. 21, 2018	Nov. 21, 2017	Jan. 31, 2017	Nov. 21, 2016	Mar. 10, 2014
Debt Instrument [Line Items]
Shares issuable under warrants granted (in shares)								187,500
Shares issuable under warrants granted (in dollars per share)								$ 1.4
Additional shares issuable under warrants granted (in shares)								112,500
Warrants exercised during period, shares issued (in shares)		168,750
Warrants exercised, shares withheld in lieu of cash (in shares)		18,750
Term Loan
Debt Instrument [Line Items]
Loan face amount								$ 10,000,000.0
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity	$ 20,000,000.0						$ 40,000,000.0	5,000,000.0
Line of credit maturity extension	1 year
Letters of credit, net of amounts pledged			$ 4,200,000
Available borrowing capacity			$ 35,800,000
Unused line of credit percentage fee			0.15%
Line of credit commitment fee					$ 100,000		$ 100,000
Draws on line of credit			$ 0			$ 0		$ 0
Revolving Credit Facility \| Line of Credit \| Prime Rate
Debt Instrument [Line Items]
Line of credit interest rate			0.75%
Scenario, Forecast \| Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Line of credit commitment fee				$ 100,000.0

Commitments and Contingencies - Narrative (Details)	1 Months Ended	12 Months Ended
Commitments and Contingencies - Narrative (Details)	Dec. 31, 2017 USD ($) renewal_option	Jan. 31, 2018 USD ($)	Jan. 31, 2017 USD ($)	Jan. 31, 2016 USD ($)	Aug. 31, 2017 USD ($)
Other Commitments [Line Items]
Lease commitment amount		$ 254,461,000
Restricted cash		8,284,000	$ 0	$ 3,673,000
Deferred rent		5,500,000	4,800,000
Rent expense		10,600,000	7,400,000	$ 5,200,000
Letter of Credit
Other Commitments [Line Items]
Letters of credit issued and outstanding		12,200,000	5,400,000
Draws on letters of credit		$ 0
San Francisco - 9 Year Lease
Other Commitments [Line Items]
Lease term		9 years
Proceeds received for tenant incentives			$ 1,800,000
Number of renewal options \| renewal_option	2
Lease renewal term	5 years
San Francisco - 10 Year Lease
Other Commitments [Line Items]
Lease term	10 years
Lease commitment amount	$ 206,300,000
Tenant improvement allowance (up to)	$ 24,700,000.0
Restricted cash		$ 8,000,000
San Jose Office Space, Amendment
Other Commitments [Line Items]
Lease commitment amount					$ 6,600,000
Tenant improvement allowance (up to)					$ 800,000.0

Commitments and Contingencies - Summary of Future Commitment Maturity Schedules (Details) $ in Thousands	Jan. 31, 2018 USD ($)
Operating Leases
2019	$ 14,105
2020	18,243
2021	24,719
2022	26,521
2023	26,487
Thereafter	144,386
Total contractual obligations	254,461
Purchase Obligations
2019	13,048
2020	13,077
2021	4,347
2022	0
2023	0
Thereafter	0
Total contractual obligations	30,472
Total
2019	27,153
2020	31,320
2021	29,066
2022	26,521
2023	26,487
Thereafter	144,386
Total contractual obligations	$ 284,933

Common Stock and Stockholders' Equity (Deficit) - Narrative (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Apr. 06, 2017 shares	Jan. 31, 2018 USD ($) vote $ / shares shares	Jan. 31, 2017 USD ($) $ / shares shares	Jan. 31, 2016 USD ($) shares
Class of Stock [Line Items]
Redeemable preferred stock outstanding (in shares)		0	0
Redeemable convertible preferred stock, shares issued (in shares)		0	59,465,439
Shares authorized (in shares)			120,000,000
Common stock, par value (in dollars per share) \| $ / shares			$ 0.0001
Non-cash charitable contributions \| $		$ 708	$ 0	$ 0
Series B Redeemable Convertible Preferred Stock
Class of Stock [Line Items]
Shares issuable under warrants granted (in shares)			29,058
Shares issuable under warrants granted (in dollars per share) \| $ / shares			$ 1.38
Fair value of warrant \| $			$ 300
Redeemable Convertible Preferred Stock
Class of Stock [Line Items]
Redeemable convertible preferred stock converted to common class B stock (in shares)	59,491,640
Redeemable preferred stock outstanding (in shares)		0
Redeemable convertible preferred stock, shares issued (in shares)		0
Class B Common Stock
Class of Stock [Line Items]
Common class B stock after conversion of redeemable convertible stock (in shares)	59,491,640
Shares authorized (in shares)		120,000,000	120,000,000
Common stock, par value (in dollars per share) \| $ / shares		$ 0.0001	$ 0.0001
Common stock outstanding (in shares)		33,361,106	20,229,000
Number of votes per share \| vote		10
Non-cash charitable contributions \| $			$ 100	$ 100
Series B Redeemable Convertible Preferred Stock
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares issued (in shares)			11,986,055
Class A Common Stock
Class of Stock [Line Items]
Shares authorized (in shares)		1,000,000,000	0
Common stock, par value (in dollars per share) \| $ / shares		$ 0.0001	$ 0.0001
Common stock outstanding (in shares)		70,609,898	0
Number of votes per share \| vote		1
Non-cash charitable contributions \| $		$ 700
Common Stock \| Class B Common Stock
Class of Stock [Line Items]
Issuance of common stock pursuant to charitable donation (in shares)		0	13,935	17,433
Common Stock \| Class A Common Stock
Class of Stock [Line Items]
Issuance of common stock pursuant to charitable donation (in shares)		24,287

Common Stock and Stockholders' Equity (Deficit) - Schedule of Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)	0	59,494,582
Redeemable convertible preferred stock, shares issued (in shares)	0	59,465,439
Redeemable convertible preferred stock, shares outstanding (in shares)	0	59,465,439	59,465,439	53,223,503
Redeemable convertible preferred stock, liquidation preference	$ 0	$ 230,373
Redeemable convertible preferred stock, carrying value	$ 0	$ 227,954	$ 227,954	$ 154,530
Series A
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)		14,210,789
Redeemable convertible preferred stock, shares issued (in shares)		14,210,783
Redeemable convertible preferred stock, shares outstanding (in shares)		14,210,783
Redeemable convertible preferred stock, liquidation preference		$ 11,373
Redeemable convertible preferred stock, carrying value		$ 11,322
Series B
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)		12,015,123
Redeemable convertible preferred stock, shares issued (in shares)		11,986,055
Redeemable convertible preferred stock, shares outstanding (in shares)		11,986,055
Redeemable convertible preferred stock, liquidation preference		$ 16,500
Redeemable convertible preferred stock, carrying value		$ 16,420
Series C
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)		10,708,782
Redeemable convertible preferred stock, shares issued (in shares)		10,708,780
Redeemable convertible preferred stock, shares outstanding (in shares)		10,708,780
Redeemable convertible preferred stock, liquidation preference		$ 25,000
Redeemable convertible preferred stock, carrying value		$ 24,872
Series D
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)		6,833,654
Redeemable convertible preferred stock, shares issued (in shares)		6,833,651
Redeemable convertible preferred stock, shares outstanding (in shares)		6,833,651
Redeemable convertible preferred stock, liquidation preference		$ 27,500
Redeemable convertible preferred stock, carrying value		$ 27,416
Series E
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)		9,484,234
Redeemable convertible preferred stock, shares issued (in shares)		9,484,234
Redeemable convertible preferred stock, shares outstanding (in shares)		9,484,234
Redeemable convertible preferred stock, liquidation preference		$ 75,000
Redeemable convertible preferred stock, carrying value		$ 74,500
Series F
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)		6,242,000
Redeemable convertible preferred stock, shares issued (in shares)		6,241,936
Redeemable convertible preferred stock, shares outstanding (in shares)		6,241,936
Redeemable convertible preferred stock, liquidation preference		$ 75,000
Redeemable convertible preferred stock, carrying value		$ 73,424

Common Stock and Stockholders' Equity (Deficit) - Schedule of Common Stock Reserved for Future Issuance (Details)	Jan. 31, 2018 shares
Class of Stock [Line Items]
Common stock reserved for future issuance and options and unvested RSUs outstanding (in shares)	40,053,526
Options and unvested RSUs outstanding
Class of Stock [Line Items]
Options and unvested RSUs outstanding (in shares)	27,779,974
Common stock, reserved for future issuance (in shares)	9,842,925
ESPP
Class of Stock [Line Items]
Common stock, reserved for future issuance (in shares)	2,430,627

Employee Incentive Plans - Schedule of Stock-based Compensation Expense by Award Type (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 49,860	$ 17,127	$ 9,832
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	24,186	17,127	9,832
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	9,104	0	0
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	7,111	0	0
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3,281	0	0
Restricted common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 6,178	$ 0	$ 0

Employee Incentive Plans - Schedule of Stock-based Compensation Expense by Statement of Operations Location (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 49,860	$ 17,127	$ 9,832
Subscription
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	4,600	1,979	909
Professional services and other
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3,137	1,283	553
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	18,107	2,992	1,748
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	13,242	6,029	2,853
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 10,774	$ 4,844	$ 3,769

Employee Incentive Plans - Narrative (Details) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Feb. 17, 2017 USD ($) shares	Mar. 31, 2017 offering_period shares	Jan. 31, 2018 USD ($) equity_incentive_plan $ / shares shares	Jan. 31, 2017 USD ($) $ / shares shares	Jan. 31, 2016 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| equity_incentive_plan			2
Options to purchase common stock outstanding (in shares) \| shares			24,917,045	32,866,862
Weighted average grant date fair value of options granted (in usd per share) \| $ / shares			$ 5.40	$ 4.00	$ 3.14
Grant date fair value of vested stock options			$ 23,900	$ 13,100	$ 7,700
Intrinsic value of options exercised			204,800	6,900	$ 4,800
Unrecognized stock-based compensation expense			$ 53,900
Number of options, granted (in shares) \| shares			2,676,667
Issuance of common stock under employee stock purchase plan			$ 8,369
Class B Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares subject to early exercise, liability recorded in accrued expenses and other current liabilities			$ 1,100	$ 2,200
Number of options subject to early exercise (in shares) \| shares			187,820	467,180
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average stock-based compensation recognition period			3 years 6 months
Granted during period (in shares) \| shares			3,012,111
Shares issued fair value			$ 73,400
Unrecognized compensation costs related to unvested restricted stock units			$ 60,400
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period (years)			10 years
Vesting period			4 years
Weighted average stock-based compensation recognition period			2 years 7 months 6 days
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, reserved for future issuance (in shares) \| shares			2,430,627
Weighted average stock-based compensation recognition period			5 months 1 day
Unrecognized compensation costs related to unvested restricted stock units			$ 4,000
Shares authorized (in shares) \| shares		3,000,000
ESPP offering period		12 months
Number of offering periods \| offering_period		2
ESPP length of purchase period		6 months
Shares issued under ESPP (in shares) \| shares			569,373
Weighted average price, shares issued under ESPP (in usd per share) \| $ / shares			$ 14.70
Stormpath Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-combination service consideration	$ 3,700
Stormpath Inc. \| Restricted common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Granted during period (in shares) \| shares	800,000
Shares issued fair value	$ 8,600
Stormpath Inc. \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average stock-based compensation recognition period			1 year
Unrecognized compensation costs related to unvested restricted stock units			$ 2,500
Stormpath Inc. \| Stormpath Workforce
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense	2,100		$ 1,600
Shares issued fair value	9,100
Pre-combination service consideration	$ 1,500
Stormpath Inc. \| Stormpath Workforce \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average stock-based compensation recognition period			1 year 6 months
Granted during period (in shares) \| shares	598,500
Shares issued fair value	$ 6,600
Unrecognized compensation costs related to unvested restricted stock units	$ 5,500		$ 2,200
Stormpath Inc. \| Stormpath Workforce \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Weighted average stock-based compensation recognition period			2 years 4 months 24 days
Shares issued fair value	$ 2,500
Number of options, granted (in shares) \| shares	518,900
Minimum \| Stormpath Inc. \| Stormpath Workforce \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Expense recognition period			2 years
Maximum \| Stormpath Inc. \| Stormpath Workforce \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Expense recognition period			3 years
2009 Stock Plan \| Class B Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock outstanding (in shares) \| shares			24,836,949
2017 Equity Incentive Plan \| Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock outstanding (in shares) \| shares			80,096
Vesting Tranche One \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Vesting percentage earned by employees after each completed year of service			25.00%

Employee Incentive Plans - Schedule of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
Number of Options
Number of options, outstanding beginning of period (in shares)	32,866,862
Number of options, granted (in shares)	2,676,667
Number of options, exercised (in shares)	(9,180,242)
Number of options, canceled (in shares)	(1,446,242)
Number of options, outstanding end of period (in shares)	24,917,045	32,866,862
Vested and expected to vest, number of options (in shares)	24,917,045
Vested and exercisable, number of options (in shares)	10,205,493
Weighted- Average Exercise Price
Options outstanding, weighted average exercise price beginning of period (in dollars per share)	$ 6.01
Options granted, weighted average exercise price (in dollars per share)	11.56
Options exercised, weighted average exercise price (in dollars per share)	3.66
Options canceled, weighted average exercise price (in dollars per share)	7.76
Options outstanding, weighted average exercise price end of period (in dollars per share)	7.37	$ 6.01
Vested and expected to vest, weighted average exercise price (in dollars per share)	7.37
Vested and exercisable, weighted average exercise price (in dollars per share)	$ 5.33
Additional Disclosures
Options outstanding, weighted average remaining contractual term	7 years 7 months 21 days	8 years 2 months 16 days
Options outstanding, aggregate intrinsic value	$ 550,173	$ 145,570
Vested and expected to vest, weighted average remaining contractual term	7 years 7 months 21 days
Vested and exercisable, weighted average remaining contractual term	6 years 10 months 24 days
Vested and expected to vest, aggregate intrinsic value	$ 550,173
Vested and exercisable, aggregate intrinsic value	$ 246,189

Employee Incentive Plans - Schedule of Black-Scholes Option Pricing Model Estimated Fair Value Assumptions (Details)	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, minimum	40.00%	40.00%	42.00%
Expected volatility, maximum	41.00%	44.00%	46.00%
Risk-free interest rate, minimum	1.87%	1.13%	1.43%
Risk-free interest rate, maximum	2.21%	2.28%	1.88%
Expected dividend yield	0.00%	0.00%	0.00%
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years 3 months 18 days	5 years 6 months	5 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years 4 months 24 days	6 years 10 months 24 days	6 years 1 month 6 days
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, minimum	32.00%
Expected volatility, maximum	38.00%
Risk-free interest rate, minimum	0.95%
Risk-free interest rate, maximum	1.73%
Expected dividend yield	0.00%
ESPP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 months
ESPP \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	1 year 2 months 12 days

Employee Incentive Plans - Schedule of Restricted Stock Unit Activity (Details) - RSUs	12 Months Ended
	Jan. 31, 2018 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding as of January 31, 2017 (in shares) \| shares	0
Granted during period (in shares) \| shares	3,012,111
Vested during period (in shares) \| shares	0
Forfeited during period (in shares) \| shares	(149,182)
Outstanding as of January 31, 2018 (in shares) \| shares	2,862,929
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Outstanding as of January 31, 2017 (in dollars per share) \| $ / shares	$ 0.00
Granted during period (in dollars per share) \| $ / shares	24.37
Vested during period (in dollars per share) \| $ / shares	0.00
Forfeited during period (in dollars per share) \| $ / shares	24.15
Outstanding as of January 31, 2018 (in dollars per share) \| $ / shares	$ 24.38

Income Taxes - Schedule of Domestic and Foreign Components of Pre-tax Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Income Tax Disclosure [Abstract]
Domestic	$ (117,368)	$ (84,938)	$ (76,953)
Foreign	2,688	1,854	946
Loss before provision for (benefit from) income taxes	$ (114,680)	$ (83,084)	$ (76,007)

Income Taxes - Schedule of Components of Provision for (Benefit from) Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Current:
Federal	$ 0	$ 0	$ 0
State	0	18	0
Foreign	183	426	295
Total current provision for income taxes	183	444	295
Deferred:
Federal	(32)	60	60
State	10	6	6
Foreign	(482)	(85)	(66)
Total deferred provision for (benefit from) income taxes	(504)	(19)	0
Total provision for (benefit from) income taxes	$ (321)	$ 425	$ 295

Income Taxes - Reconciliation of Effective Income Tax Rate (Details)	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Income Tax Disclosure [Abstract]
Tax at federal statutory rate	33.80%	34.00%	34.00%
State income taxes, net of federal benefit	3.30%	3.30%	2.70%
Change in valuation allowance	(23.50%)	(32.40%)	(33.80%)
Stock-based compensation	39.90%	(4.50%)	(3.10%)
Tax Cuts and Jobs Act of 2017	(53.20%)	0.00%	0.00%
Other, net	(0.10%)	(0.90%)	(0.20%)
Effective tax rate	0.20%	(0.50%)	(0.40%)

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Deferred tax assets:
Net operating loss carryforwards	$ 123,013	$ 98,587
Stock-based compensation	7,926	3,611
Deferred revenue	1,391	4,497
Other reserves and accruals	3,084	3,768
Credits	791	625
Total deferred tax assets	136,205	111,088
Valuation allowance	(125,874)	(98,379)
Total deferred tax assets, net	10,331	12,709
Deferred tax liabilities:
Deferred commissions	(6,849)	(8,802)
Capitalized internal-use software costs	(2,389)	(2,816)
Goodwill	(175)	(196)
Depreciation and amortization	(441)	(953)
Total deferred tax liabilities	(9,854)	(12,767)
Net deferred tax asset	$ 477
Net deferred tax liabilities		$ (58)

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Jan. 31, 2018	Jan. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax benefit related to stock based compensation	$ 1,300,000
Increase in valuation allowance	27,500,000	$ 26,900,000
Reduction in deferred tax asset before valuation allowance due to change in tax rate	61,000,000
Accrued penalties and interest related to unrecognized tax benefits	0	0
Domestic Tax Authority
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating loss carryforwards	490,600,000	264,700,000
State and Local Jurisdiction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating loss carryforwards	295,600,000	$ 164,200,000
Foreign Tax Authority
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating loss carryforwards	2,300,000
Research Tax Credit Carryforward \| Domestic Tax Authority
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax credit carryforward	6,200,000
Research Tax Credit Carryforward \| State and Local Jurisdiction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax credit carryforward	5,600,000
California Enterprise Zone Credit \| State and Local Jurisdiction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax credit carryforward	$ 1,000,000

Income Taxes - Unrecognized Tax Benefits Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross amount of unrecognized tax benefits as of the beginning of the year	$ 5,775	$ 3,512	$ 1,889
Additions based on tax positions related to current year	5,944	2,263	1,623
Gross amount of unrecognized tax benefits as of the end of the year	$ 11,719	$ 5,775	$ 3,512

Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Numerator:
Net loss	$ (114,359)	$ (83,509)	$ (76,302)
Denominator:
Weighted-average shares outstanding, basic and diluted (in shares)	83,004	19,038	17,817
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (1.38)	$ (4.39)	$ (4.28)
Class A Common Stock
Denominator:
Weighted-average shares outstanding, basic and diluted (in shares)	24,165	0	0
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (1.38)	$ 0.00	$ 0.00
Class B Common Stock
Denominator:
Weighted-average shares outstanding, basic and diluted (in shares)	58,839	19,038	17,817
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (1.38)	$ (4.39)	$ (4.28)
Common Stock \| Class A Common Stock
Numerator:
Net loss	$ (33,293)	$ 0	$ 0
Common Stock \| Class B Common Stock
Numerator:
Net loss	$ (81,066)	$ (83,509)	$ (76,302)

Net Loss Per Share - Schedule of Potentially Dilutive Securities Excluded from Computation of Diluted Per Share (Details) - shares shares in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	30,516	92,548	81,682
Restricted common stock issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	800	0	0
Unvested RSUs issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	2,863	0	0
Unvested restricted stock awards issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	599	0	0
Shares committed under the ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	1,149	0	0
Unvested shares subject to repurchase
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	188	0	0
Conversion of convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0	59,465	59,465
Issued and outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	24,917	32,866	22,000
Conversion of common stock warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0	188	188
Conversion of convertible Series B warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0	29	29

Subsequent Events - Narrative (Details) - Subsequent Event	Feb. 27, 2018 USD ($) $ / shares	Feb. 22, 2018 USD ($) $ / shares	Feb. 23, 2018 USD ($)
Subsequent Event [Line Items]
Proceeds from issuance of warrants	$ 52,400,000
Aggregate amount paid for cost of Note Hedge	80,000,000
Warrant strike price (in dollars per share) \| $ / shares		$ 68.06
Strike price of warrants, premium percentage		90.00%
Initial Notes \| Senior Notes
Subsequent Event [Line Items]
Aggregate principal amount		$ 300,000,000	$ 345,000,000
Net proceeds	$ 334,000,000
Interest rate	0.25%
Initial conversion rate of common stock	0.0206795
Conversion price (in dollars per share) \| $ / shares	$ 48.36
Redemption price percentage	100.00%
Additional Notes \| Senior Notes
Subsequent Event [Line Items]
Aggregate principal amount			$ 45,000,000

Related Party Transactions	12 Months Ended
Related Party Transactions	Jan. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Certain members of the Company's board of directors serve as directors of and/or are executive officers of and, in some cases, are investors in, companies that are customers or vendors of the Company. Certain of the Company’s executive officers also serve as directors of or serve in an advisory capacity to companies that are customers or vendors of the Company. Related party transactions were not material as of and for the years ended January 31, 2018, 2017 and 2016.

CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Parenthetical) $ in Thousands	12 Months Ended
	Jan. 31, 2016 USD ($)
Payments of stock issuance costs	$ 0
Series F Redeemable Convertible Preferred Stock
Payments of stock issuance costs	$ 1,576