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Class B Common Stock Common Class B [Member] Violation Of Securities Act Section 10(b), 20(a), and Rule 10b-5 Violation Of Securities Act Section 10(b), 20(a), and Rule 10b-5 [Member] Violation Of Securities Act Section 10(b), 20(a), and Rule 10b-5 Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Net income attributable to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Weighted- Average Remaining Contractual Life (Years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Marketable securities Estimated Fair Value Total Debt Securities, Available-for-sale Restricted cash, noncurrent included in other assets, noncurrent Restricted Cash and Cash Equivalents, Noncurrent Deferred contract acquisition costs, noncurrent Capitalized Contract Cost, Net, Noncurrent Corporate and other debt securities Corporate Bond Securities [Member] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Retained earnings Retained Earnings (Accumulated Deficit) Entity Tax Identification Number Entity Tax Identification Number Debt instrument face amount Debt Instrument, Face Amount Diluted (in dollars per share) Net income per share attributable to common stockholders, diluted (in dollars per share) Earnings Per Share, Diluted Unrealized gain on available-for-sale marketable securities, net of tax Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax Accounts receivable, noncurrent Accounts Receivable, after Allowance for Credit Loss, Noncurrent Sales and marketing Selling and Marketing Expense Trading Symbol Trading Symbol Available for Sale Investments Marketable Securities, Policy [Policy Text Block] Entity Information [Line Items] Entity Information [Line Items] Class A Common Stock Common Class A [Member] Investments, Debt and Equity Securities [Abstract] Undistributed earnings attributable to participating securities Undistributed Earnings (Loss) Allocated to Participating Securities, Basic Debt instrument term Debt Instrument, Term Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Summary of Stock Option Activity Under Equity Incentive Plan Share-based Payment Arrangement, Option, Activity [Table Text Block] Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Options outstanding, aggregate intrinsic value, vested and exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Provision for income taxes Income Tax Expense (Benefit) 2011 Plan Two Thousand Eleven Equity Incentive Plan [Member] Two thousand eleven equity incentive plan. 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Issuance of common stock upon exercise of stock options Stock Issued During Period, Value, Stock Options Exercised Depreciation and amortization expense Depreciation, Depletion and Amortization, Nonproduction Americas Americas [Member] Deferred contract acquisition costs Increase Decrease In Deferred Contract Acquisition Costs Increase decrease in Deferred contract acquisition costs. Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Income Statement Location Income Statement Location [Domain] Annual increase in Number of shares of common stock available for future issuance Annual Increase In Number Of Shares Of Common Stock For Available For Future Issuance Annual increase in Number of shares of common stock available for future issuance. 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Interest rate percentage Debt Instrument, Interest Rate, Stated Percentage Entity Address, Address Line One Entity Address, Address Line One Agency bonds Municipal Bonds [Member] Property and equipment, gross Property, Plant and Equipment, Gross Deferred contract acquisition costs, current Capitalized Contract Cost, Net, Current Percentage of purchase price of common stock to fair market value of common stock on offering or purchase date Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Gross profit Gross Profit Geographical Geographical [Domain] Entity Address, State or Province Entity Address, State or Province Income Statement Location Income Statement Location [Axis] Summary of Contractual Maturities of Marketable Securities Investments Classified by Contractual Maturity Date [Table Text Block] Initial public offering IPO [Member] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Other Other Operating Activities, Cash Flow Statement General and administrative General and Administrative Expense Accounts payable Accounts Payable, Current Accrued expenses Accrued Liabilities, Current Schedule of Accrued Expenses and Other Current Liabilities Accrued Expenses And Other Current Liabilities [Table Text Block] Accrued expenses and other current liabilities. 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Annual Increase In Shares For Available For Future Issuance By Percentage Of Outstanding Ordinary Shares On Last Day Of Such Fiscal Year Annual increase in shares for available for future issuance by percentage of the outstanding ordinary shares on the last day of such fiscal year. 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Weighted average price per share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased Marketable Securities [Line Items] Marketable Securities [Line Items] Cost of revenue Cost of Sales [Member] RSUs Unvested RSUs Restricted Stock Units (RSUs) [Member] Research and development Research and Development Expense [Member] Cloud Computing Arrangement Implementation Costs Research, Development, and Computer Software, Policy [Policy Text Block] Effective tax rate Effective Income Tax Rate Reconciliation, Percent Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] ESPP excess rate purchase right, value Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Amount Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Amount Schedule of Provision for Income Taxes Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Total liabilities Liabilities Accrued compensation and benefits Accrued Employee Benefits, Current Prepaid Expenses and Other Current Assets Prepaid Expenses and Other Current Assets [Table Text Block] Prepaid Expenses and Other Current Assets Common stock, $0.001 par value per share, 2,000,000,000 Class A shares authorized as of April 30, 2020 and January 31, 2020; 167,647,512 and 123,391,114 shares issued and outstanding as of April 30, 2020 and January 31, 2020, respectively; 300,000,000 Class B shares authorized as of April 30, 2020 and January 31, 2020; 114,344,499 and 155,336,747 shares issued and outstanding as of April 30, 2020 and January 31, 2020, respectively Common Stock, Value, Issued Maturities of marketable securities Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Sales and marketing Selling and Marketing Expense [Member] Reconciliation of cash, cash equivalents, and restricted cash within the condensed consolidated balance sheets to the amounts shown in the condensed consolidated statements of cash flows above: Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] Research and development Research and Development Expense Loss contingency, number of defendants Loss Contingency, Number of Defendants Cancelled/forfeited/expired (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Issuance of common stock upon exercise of stock options, net of repurchases Stock Issued Durring Period Value Issuance Of Common Stock Upon Exercise Of Stock Options Net Of Repurchases Stock issued durring the period, value, issuance of common stock upon exercise of stock options, net of repurchases. Statement of Comprehensive Income [Abstract] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Issuance of restricted shares of common stock Restricted Stock, Value, Shares Issued Net of Tax Withholdings Cash and cash equivalents Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Basic (in shares) Weighted-average shares used in computing net income per share attributable to common stockholders, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Sales and other tax liabilities Sales And Other Tax Liabilities Current Sales and other tax liabilities current. Equity Components Equity Components [Axis] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Purchase of equity investment Payments to Acquire Equity Method Investments Total stockholders’ equity Beginning balance Ending balance Stockholders' Equity Attributable to Parent Common stock, capital shares reserved for future issuance, charitable donation (in shares) Common Stock, Capital Shares Reserved for Future Issuance, Charitable Donation Common Stock, Capital Shares Reserved for Future Issuance, Charitable Donation Cancelled/forfeited (in units) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Percentage of shares reserved increase Percentage Of Share Based Compensation Arrangements By Share Based Payment Award Options Increase In Shares Reserved For Issuance Percentage of share based compensation arrangements by share based payment award options increase in shares reserved for issuance. Allowance for Credit Losses Credit Loss, Financial Instrument [Policy Text Block] Deferred revenue, current Contract with Customer, Liability, Current Asia Pacific (“APAC”) Asia Pacific [Member] Convertible Debt Convertible Debt [Member] Summary of Business and Significant Accounting Policies Business Description and Accounting Policies [Text Block] Fair Value Measurements Fair Value Disclosures [Text Block] Europe, Middle East, and Africa (“EMEA”) EMEA [Member] Depreciation and amortization Depreciation, Depletion and Amortization Conversion of convertible preferred stock to common stock upon initial public offering Stock Issued During Period, Value, Conversion of Convertible Securities Preferred stock Preferred Stock, Value, Issued Less: allowance for credit losses Beginning balance Ending balance Accounts Receivable, Allowance for Credit Loss Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Sales and other tax liabilities Sales And Other Tax Liabilities Non Current Sales and other tax liabilities non current. Security Exchange Name Security Exchange Name Antidilutive securities excluded from computation of earnings per share, amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Equity investment Equity Method Investments Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Additional paid-in capital Additional Paid in Capital, Common Stock Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Equity Component Equity Component [Domain] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Deferred revenue Increase (Decrease) in Contract with Customer, Liability Document Transition Report Document Transition Report Number of offering dates Share-Based Compensation Arrangement By Share-based Payment Award, Number of Offering Dates Share-Based Compensation Arrangement By Share-based Payment Award, Number of Offering Dates Share-based Payment Arrangement, Option Share-based Payment Arrangement, Option [Member] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Liabilities to employees and tax authorities from international employee stock sales Employee-related Liabilities, Employee Stock Sales, Current Employee-related Liabilities, Employee Stock Sales, Current Less: allowance for returns Accounts Receivables, Allowance for Returns Accounts Receivables, Allowance for Returns Net income (loss) attributable to common stockholders, diluted Net Income (Loss) Available to Common Stockholders, Diluted Common stock, shares reserved for charitable donations, fair value, amount Common Stock, Shares Reserved for Charitable Donations, Fair Value, Amount Common Stock, Shares Reserved for Charitable Donations, Fair Value, Amount Accounts Receivable, Allowance for Credit Loss [Roll Forward] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Employee Stock Purchase Plan Employee Stock [Member] Issuance of restricted shares of common stock, net (in shares) Restricted Stock, Shares Issued Net of Shares for Tax Withholdings Income Statement [Abstract] Charitable donation of common stock Donation of Common Stock to Charitable Foundation Donation of Common Stock to Charitable Foundation Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Proceeds from unvested shares of common stock Proceeds From Unvested Shares Of Common Stock Proceeds from unvested shares of common stock.