Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Apr. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation	The interim unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and include the accounts of the Company and its wholly owned subsidiaries. All intercompany transactions and accounts have been eliminated. Certain information and note disclosures normally included in the financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to the applicable rules and regulations of the Securities and Exchange Commission (“SEC”). Therefore, these interim unaudited condensed consolidated financial statements and accompanying footnotes should be read in conjunction with the Company’s annual consolidated financial statements and related footnotes included in its Annual Report on Form 10-K for the fiscal year ended January 31, 2018 (the “2018 Form 10-K”).
Use of Estimates	The preparation of the interim unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting period. Such estimates include, but are not limited to, revenue recognition, allowances for doubtful accounts, stock-based compensation, legal contingencies, fair value of acquired intangible assets and goodwill, useful lives of acquired intangible assets and property and equipment, fair value of property and equipment and accounting for income taxes. The Company bases these estimates on historical and anticipated results, trends and various other assumptions that it believes are reasonable under the circumstances, including assumptions as to future events. Actual results could differ from those estimates.
Emerging Growth Company Status	As an “emerging growth company” (“EGC”), the Jump-start Our Business Start-ups Act (“JOBS Act”), allows the Company to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies. The Company has elected to use this extended transition period under the JOBS Act. As a result, the Company’s financial statements may not be comparable to the financial statements of issuers who are required to comply with the effective dates for new or revised accounting standards that are applicable to public companies, which may make the Company’s common stock less attractive to investors.
Related Party Transactions	All contracts with related parties are executed in ordinary course of business.
New Accounting Pronouncements Not Yet Adopted	Goodwill Impairment. In January 2017, the Financial Accounting Standards Board (“FASB”) issued ASU 2017-04—Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. The new standard will simplify the measurement of goodwill by eliminating step two of the two-step impairment test. Step two measures a goodwill impairment loss by comparing the implied fair value of a reporting unit’s goodwill with the carrying amount of that goodwill. The new guidance requires an entity to compare the fair value of a reporting unit with its carrying amount and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. Additionally, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when measuring the goodwill impairment loss, if applicable. The new guidance becomes effective for the Company for the fiscal year ending January 31, 2022, though early adoption is permitted. The Company does not expect the adoption of the new accounting standard to have a material impact on its consolidated financial statements. Leases. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which modifies lease accounting for lessees to increase transparency and comparability by recording lease assets and liabilities for operating leases and disclosing key information about leasing arrangements. Depending on when the Company loses its EGC status, it may be required to adopt the new lease standard as early as its interim results for the period ending April 30, 2019, but no later than for its annual results for the fiscal year ending January 31, 2021, though early adoption is permitted. The Company is currently evaluating adoption methods and whether this standard will have a material impact on its consolidated financial statements. Revenue Recognition. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which amends the existing accounting standard for revenue recognition. ASU 2014-09 is based on principles that govern the recognition of revenue at an amount to which an entity expects to be entitled when products are transferred to customers. Subsequently, the FASB has issued the following pronouncements related to ASU 2014-09: ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations; ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing; ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients; and ASU 2016-20, Technical Corrections and Improvements to Topic 606, which clarifies narrow aspects of ASC 606 or corrects unintended application of the guidance. The Company must adopt ASU 2016-08, ASU 2016-10, ASU 2016-12, and ASU 2016-20 with ASU 2014-09 (collectively, the “new revenue standard”). The Company plans to adopt the new revenue standard using the full retrospective transition method when it becomes effective for the Company. Depending on when the Company loses its EGC status, it may be required to adopt the new revenue standard as early as its annual results for the fiscal year ending January 31, 2019, but no later than for its annual results for the fiscal year ending January 31, 2020, though early adoption is permitted. While the Company continues to assess the potential impacts of the new revenue standard, the Company currently expects unearned subscription revenue to decline significantly upon adoption. Currently, as the Company’s subscription offerings include software term licenses and post-contract customer support for which the Company has not established vendor specific objective evidence (“VSOE”), the entire subscription fee is recognized ratably over the term of the contract. However, under the new revenue standard, the requirement for VSOE for undelivered elements is eliminated and, as a result, the Company is required to identify all deliverables in a contract and recognize revenue based on each deliverable separately. The Company currently expects that the portion related to the software term license deliverable will be recognized upon delivery, which may result in greater fluctuations in its consolidated financial statements. The Company is in the process of determining the revenue recognition impact for the other deliverables of each contract. The Company continues to evaluate the effect that the new revenue standard will have on its consolidated financial statements and related disclosures, and preliminary assessments are subject to change.
Net Loss per Share	The Company calculates basic net loss per share by dividing the net loss by the weighted-average number of shares of common stock outstanding during the period, less shares subject to repurchase. Diluted net loss per share is computed by giving effect to all potentially dilutive common stock equivalents outstanding for the period, including stock options and restricted stock units. Prior to the Company’s closing of its initial public offering in October 2017, the Company calculated basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for companies with participating securities. The Company considered all series of redeemable convertible preferred stock to have been participating securities as the holders were entitled to receive non-cumulative dividends on a pari passu basis in the event that a dividend had been paid on common stock. For further details on the Company’s historical participating securities, including warrants to purchase redeemable convertible preferred stock and common stock, refer to the Company’s 2018 Form 10-K, specifically in Part II, Item 8, Financial Statements and Supplementary Data under the Notes to Consolidated Financial Statements. Under the two-class method, basic net loss per share attributable to common stockholders was calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding during the period, less shares subject to repurchase. The net loss attributable to common stockholders was not allocated to the redeemable convertible preferred stock as the holders of redeemable convertible preferred stock did not have a contractual obligation to share in losses. Diluted net loss per share attributable to common stockholders was computed by giving effect to all potentially dilutive common stock equivalents outstanding for the period. For purposes of this calculation, redeemable convertible preferred stock, stock options to purchase common stock, early exercised stock options, and warrants to purchase redeemable convertible preferred stock and common stock were considered common shares equivalents, but had been excluded from the calculation of diluted net loss per share attributable to common stockholders as their effect was antidilutive. Basic and diluted net loss per share was the same for each period presented, as the inclusion of all potential common shares outstanding would have been antidilutive. The rights, including the liquidation and dividend rights, of the holders of Class A and Class B common stock are identical, except with respect to voting. Each share of Class A common stock is entitled to one vote per share and each share of Class B common stock is entitled to 10 votes per share. As the liquidation and dividend rights are identical for Class A and Class B common stock, the undistributed earnings are allocated on a proportionate basis and the resulting net loss per share will, therefore, be the same for both Class A and Class B common stock on an individual or combined basis.
Income Taxes	The Company assesses uncertain tax positions in accordance with ASC 740-10, Accounting for Uncertainties in Tax.

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.