Cash and Cash Equivalents [Abstract] Schedule of Cash, Cash Equivalents and Short-Term Investments Cash, Cash Equivalents and Investments [Table Text Block] Contractual Maturities of Short Term Investments Investments Classified by Contractual Maturity Date [Table Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill Goodwill Disclosure [Text Block] Statement of Financial Position [Abstract] Non-current deferred rent Deferred Rent Credit, Noncurrent Property, Plant and Equipment [Abstract] Schedule of Property and Equipment, Net Property, Plant and Equipment [Table Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Equity investments Equity Securities, FV-NI Gain on equity investments Equity Securities, FV-NI, Gain (Loss) Business Combinations [Abstract] Business Combinations Business Combination Disclosure [Text Block] Earnings Per Share [Abstract] Net Loss Per Share Earnings Per Share [Text Block] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] HelloSign Inc. HelloSign Inc. [Member] HelloSign Inc. [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Purchase consideration, agreements with key personnel Business Combination, Separately Recognized Transactions, Preexisting Relationship, Personnel Agreement Business Combination, Separately Recognized Transactions, Preexisting Relationship, Personnel Agreement Acquired finite-lived intangible assets weighted average amortization period Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Transaction costs Business Combination, Acquisition Related Costs Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES International Non-US [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Property and equipment, net Property, Plant and Equipment, Net Revenue Revenue from Contract with Customer, Excluding Assessed Tax Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] Preferred Stockholders and Vested Option Holders Preferred Stockholders And Vested Option Holders [Member] Preferred Stockholders And Vested Option Holders [Member] HelloSign HelloSign [Member] HelloSign [Member] Cash and transaction costs paid Payments to Acquire Businesses, Gross Fair value of assumed HelloSign options attributable to pre-combination services (1) Business Combination, Consideration Transferred, Stock Options Assumed Business Combination, Consideration Transferred, Stock Options Assumed Purchase price adjustments Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred Total purchase consideration Business Combination, Consideration Transferred Leases [Abstract] Components of Lease Expense and Other Information Lease, Cost [Table Text Block] Maturities of Operating Lease Liabilities Finance Lease, Liability, Maturity [Table Text Block] Maturities of Finance Lease Liabilities Lessee, Operating Lease, Liability, Maturity [Table Text Block] Cash in transit for credit and debit card transactions Credit and Debit Card Receivables, at Carrying Value Number of investments in unrealized loss positions Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions Other-than-temporary impairment loss Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale Interest income Investment Income, Net Fair Value Disclosures [Abstract] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Recurring [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 Fair Value, Inputs, Level 1 [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Money market funds Money Market Funds [Member] US Treasury securities US Treasury Securities [Member] Asset-backed securities Asset-backed Securities [Member] Commercial paper Commercial Paper [Member] Cash equivalents Cash Equivalents [Member] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Corporate notes and obligations Corporate Debt Securities [Member] Certificates of deposit Certificates of Deposit [Member] US Agency securities US Government Corporations and Agencies Securities [Member] Municipal securities Municipal Bonds [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Total cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Total short-term investments Debt Securities, Available-for-sale Total cash equivalents and short-term investments Cash Equivalents, And Short-term Investments Cash Equivalents, and Short-term Investments Total Assets, Fair Value Disclosure Debt Disclosure [Abstract] Revolving Credit Facility Debt Disclosure [Text Block] Property and Equipment, Net Property, Plant and Equipment Disclosure [Text Block] Non-trade receivables Nontrade Receivables, Current Conversion of Stock [Table] Conversion of Stock [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Two-Tier RSUs Two-Tier Restricted Stock Units (RSUs) [Member] Two-Tier Restricted Stock Units (RSUs) [Member] Sale of Stock [Axis] Sale of Stock [Axis] Sale of Stock [Domain] Sale of Stock [Domain] Private Placement Private Placement [Member] Underwriters Over-allotment Option Over-Allotment Option [Member] Stock Conversion Description [Axis] Stock Conversion Description [Axis] Conversion of Stock, Name [Domain] Conversion of Stock, Name [Domain] Conversion of Convertible Preferred Stock to Class B Common Stock Conversion Of Convertible Preferred Stock To Class B Common Stock [Member] Conversion Of Convertible Preferred Stock To Class B Common Stock [Member] Conversion of Convertible Preferred Stock to Class A Common Stock Conversion Of Convertible Preferred Stock To Class A Common Stock [Member] Conversion Of Convertible Preferred Stock To Class A Common Stock [Member] Conversion of Class B Common Stock to Class A Common Stock Conversion Of Class B Common Stock To Class A Common Stock [Member] Conversion Of Class B Common Stock To Class A Common Stock [Member] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Convertible preferred stock Convertible Preferred Stock [Member] Class B common stock Common Class B [Member] Class A common stock Common Class A [Member] Conversion of Stock [Line Items] Conversion of Stock [Line Items] Stock issued in IPO (in shares) Stock Issued During Period, Shares, New Issues Share price of stock issued in IPO (in dollars per share) Shares Issued, Price Per Share Proceeds from initial public offering and private placement Proceeds from Issuance Initial Public Offering Offering costs Payments of Stock Issuance Costs Shares converted in conversion (in shares) Conversion of Stock, Shares Converted Shares issued in conversion (in shares) Conversion of Stock, Shares Issued Sale of stock (in shares) Sale of Stock, Number of Shares Issued in Transaction Share price of stock sold in shares (in dollars per share) Sale of Stock, Price Per Share Proceeds received in sale of stock Sale of Stock, Consideration Received on Transaction Recognized cumulative unrecognized stock-based compensation Share-based Payment Arrangement, Accelerated Cost Shares released (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number Employer related payroll expense Labor and Related Expense Reverse stock split ratio Stockholders' Equity Note, Stock Split, Conversion Ratio Stockholders' Equity Note [Abstract] Stockholders' Equity Shareholders' Equity and Share-based Payments [Text Block] Cover page. Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Class C common stock Common Class C [Member] Class of Stock [Line Items] Class of Stock [Line Items] Document Type Document Type Document Quarterly Report Document Quarterly Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Lease Arrangements [Axis] Lease Arrangements [Axis] Lease Arrangements [Axis] Lease Arrangements [Domain] Lease Arrangements [Domain] [Domain] for Lease Arrangements [Axis] Corporate Headquarters Lease Corporate Headquarters Lease [Member] Corporate Headquarters Lease [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Payments for operating leases included in cash from operating activities Operating Lease, Payments Payments for finance leases included in cash from operating activities Finance Lease, Interest Payment on Liability Payments for finance leases included in cash from financing activities Finance Lease, Principal Payments Assets obtained in exchange for lease obligations: operating leases Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Assets obtained in exchange for lease obligations: finance leases Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Weighted average remaining lease term (in years) - operating leases Operating Lease, Weighted Average Remaining Lease Term Weighted average remaining lease term (in years) - finance leases Finance Lease, Weighted Average Remaining Lease Term Weighted average discount rate - operating leases Operating Lease, Weighted Average Discount Rate, Percent Weighted average discount rate - finance leases Finance Lease, Weighted Average Discount Rate, Percent Revenue, performance obligation, description of timing Revenue, Performance Obligation, Description of Timing Revenue recognized Contract with Customer, Liability, Revenue Recognized Remaining performance obligation Revenue, Remaining Performance Obligation, Amount Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Performance obligation satisfaction period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Concentration Risk [Table] Concentration Risk [Table] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Trade and Other Receivables Accounts Receivable And Other Receivable [Member] Accounts Receivable And Other Receivable [Member] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Customer Concentration Risk Customer Concentration Risk [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Customer A Customer A [Member] Customer A [Member] Customer B Customer B [Member] Customer B [Member] Concentration Risk [Line Items] Concentration Risk [Line Items] Amortization of deferred commissions Capitalized Contract Cost, Amortization Concentration risk, percentage Concentration Risk, Percentage Foreign currency transaction losses Foreign Currency Transaction Gain (Loss), before Tax Leases Lessee, Operating Leases [Text Block] Leases Lessee, Finance Leases [Text Block] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Datacenter and other computer equipment Computer Equipment [Member] Office equipment and other Office Equipment [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property and equipment, useful life Property, Plant and Equipment, Useful Life Schedule of Estimated Useful Lives of Property and Equipment New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2016-02 Accounting Standards Update 2016-02 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Operating lease right-of-use asset Operating Lease, Right-of-Use Asset Operating lease, liability Operating Lease, Liability Convertible preferred stock Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Co-Founder Grants Co-Founder Grants [Member] Co-Founder Grants [Member] Restricted Stock Restricted Stock [Member] Votes per share Common Stock, Vote Equivalent Common Stock, Vote Equivalent Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Shares granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Title of Individual [Axis] Title of Individual [Axis] Title of Individual [Domain] Title of Individual [Domain] Chief Executive Officer Chief Executive Officer [Member] Director Director [Member] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Tranche One Share-based Payment Arrangement, Tranche One [Member] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] One-Tier RSU One-Tier Restricted Stock Units (RSUs) [Member] One-Tier Restricted Stock Units (RSUs) [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Expiration period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Number of tranches Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Tranches Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Tranches Percentage vested maximum Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Weighted average grant date fair value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Option, Nonvested, Weighted Average Exercise Price Unamortized stock-based compensation, requisite service period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Stock-based compensation related to the Co-Founder Grants Share-based Payment Arrangement, Expense Remaining unamortized stock-based compensation Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Incremental stock based compensation Share-based Payment Arrangement, Plan Modification, Incremental Cost Goodwill [Roll Forward] Goodwill [Roll Forward] Beginning balance Goodwill HelloSign acquisition Goodwill, Acquired During Period Effect of foreign currency translation Goodwill, Foreign Currency Translation Gain (Loss) Ending balance Goodwill impairment Goodwill, Impairment Loss Schedule of Intangible Assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Schedule of Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Employee Stock Option Share-based Payment Arrangement, Option [Member] Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Risk-free interest rate, minimum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Risk-free interest rate, maximum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Income Statement [Abstract] Statement [Table] Statement [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of revenue Cost of Sales [Member] Research and development Research and Development Expense [Member] Sales and marketing Selling and Marketing Expense [Member] General and administrative General and Administrative Expense [Member] Statement [Line Items] Statement [Line Items] Allocated share-based compensation expense Payables and Accruals [Abstract] Schedule Of Accrued And Other Current Liabilities Schedule of Accrued Liabilities [Table Text Block] Assets acquired: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract] Cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Short-term investments Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities Acquisition-related intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Accounts receivable, prepaid and other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables, Prepaid Expense And Other Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables, Prepaid Expense And Other Assets Total assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Liabilities assumed: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Accounts payable, accrued and other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Deferred revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Deferred tax liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities, Current Total liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Net assets acquired, excluding goodwill Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Total purchase consideration Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Goodwill Description of the Business and Summary of Significant Accounting Policies Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Cost of revenue Cost of Goods and Services Sold Gross profit Gross Profit Operating expenses Operating Expenses [Abstract] Research and development Research and Development Expense Sales and marketing Selling and Marketing Expense General and administrative General and Administrative Expense Total operating expenses Operating Expenses Loss from operations Operating Income (Loss) Interest income, net Interest Income (Expense), Nonoperating, Net Other income, net Other Nonoperating Income (Expense) Loss before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Benefit from (provision for) income taxes Income Tax Expense (Benefit) Net loss Net Income (Loss) Attributable to Parent Net loss per share attributable to common stockholders, basic and diluted (in dollars per share) Earnings Per Share, Basic and Diluted Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted (in shares) Weighted Average Number of Shares Outstanding, Basic and Diluted Operating lease cost Operating Lease, Cost Finance lease cost: Lessee, Finance Lease, Description [Abstract] Amortization of assets under finance lease Finance Lease, Right-of-Use Asset, Amortization Interest Finance Lease, Interest Expense Total finance lease cost Finance Lease, Cost Finance Lease, Cost Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Datacenter and other computer equipment Furniture and fixtures Furniture and Fixtures [Member] Leasehold improvements Leasehold Improvements [Member] Construction in process Construction in Progress [Member] Property and equipment, gross Property, Plant and Equipment, Gross Accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, net Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Assets Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Short-term investments Debt Securities, Available-for-sale, Current Trade and other receivables, net Accounts Receivable, after Allowance for Credit Loss, Current Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Other assets Other Assets, Noncurrent Total assets Assets Liabilities and stockholders’ equity Liabilities and Equity [Abstract] Liabilities Liabilities [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued and other current liabilities Accrued Liabilities and Other Liabilities, Current Accrued Liabilities and Other Liabilities, Current Accrued compensation and benefits Employee-related Liabilities, Current Operating lease liability Operating Lease, Liability, Current Finance lease obligation Finance Lease, Liability, Current Finance lease obligation Capital Lease Obligations, Current Deferred revenue Contract with Customer, Liability, Current Total current liabilities Liabilities, Current Operating lease liability, non-current Operating Lease, Liability, Noncurrent Finance lease obligation, non-current Finance Lease, Liability, Noncurrent Finance lease obligation, non-current Capital Lease Obligations, Noncurrent Other non-current liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 10) Commitments and Contingencies Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Additional paid-in capital Additional Paid in Capital Accumulated deficit Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders’ equity Liabilities and Equity 2018 Plan 2018 Plan [Member] 2018 Plan [Member] 2008 Equity Incentive Plan, 2017 Equity Incentive Plan, and 2018 Plan 2008 Equity Incentive Plan, 2017 Equity Incentive Plan, and 2018 Plan [Member] 2008 Equity Incentive Plan, 2017 Equity Incentive Plan, and 2018 Plan [Member] Options granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Shares issued and outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Shares available for grant (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Fair value of equity instruments other than options Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Capitalized Contract Cost [Table] Capitalized Contract Cost [Table] Capitalized Contract Cost [Axis] Capitalized Contract Cost [Axis] Capitalized Contract Cost [Domain] Capitalized Contract Cost [Domain] Deferred Commissions Deferred Commissions [Member] Deferred Commissions [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Prepaid Expenses and Other Current Assets Prepaid Expenses and Other Current Assets [Member] Other Assets Other Noncurrent Assets [Member] Capitalized Contract Cost [Line Items] Capitalized Contract Cost [Line Items] Additional contract costs deferred Capitalized Contract Costs, Additions Capitalized Contract Costs, Additions Deferred contract costs Capitalized Contract Cost, Net Deferred contract costs, amortization period Capitalized Contract Cost, Amortization Period Impairment loss related to deferred costs Capitalized Contract Cost, Impairment Loss Long-lived Assets by Geographic Areas Long-lived Assets by Geographic Areas [Table Text Block] Revenue by Geographic Areas Revenue from External Customers by Geographic Areas [Table Text Block] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Controlling Shareholders Majority Shareholder [Member] Related Party Transaction [Axis] Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Dropbox Charitable Foundation Dropbox Charitable Foundation [Member] Dropbox Charitable Foundation [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Number of controlling shareholders in related party transaction Related Party Transaction, Number Of Controlling Shareholders Related Party Transaction, Number Of Controlling Shareholders Payments to related party Related Party Transaction, Amounts of Transaction Schedule of Stock Option and Restricted Stock Activity Share-based Payment Arrangement, Activity [Table Text Block] Schedule of Pre-Tax Intrinsic Value Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Fair Value of Stock Options Assumptions Used Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of Fair Value Assets Measured On Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Intangible Assets Intangible Assets Disclosure [Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Restricted stock units Options to purchase shares of common stock Shares subject to repurchase from early-exercised options and unvested restricted stock Shares Subject To Repurchase [Member] Shares Subject To Repurchase [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive securities excluded from computation of earnings per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Income tax expense (benefit) Deferred tax liability Deferred Tax Liabilities, Net Increase in unrecognized tax benefits Unrecognized Tax Benefits, Period Increase (Decrease) Unrecognized tax benefits that would impact effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate During The Period Unrecognized Tax Benefits that Would Impact Effective Tax Rate During The Period Statement of Stockholders' Equity [Abstract] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Class A and Class B common stock Common Stock [Member] Additional paid-in capital Additional Paid-in Capital [Member] Accumulated deficit Retained Earnings [Member] Accumulated other comprehensive income (loss) AOCI Attributable to Parent [Member] Convertible preferred stock Preferred Stock [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Shares outstanding, beginning of the period (in shares) Shares, Outstanding Shareholders equity, beginning balance Cumulative effect of new accounting principle Cumulative Effect of New Accounting Principle in Period of Adoption Release of restricted stock units (in shares) Shares Released During Period, Shares Shares Released During Period, Shares Shares repurchased for tax withholdings on release of restricted stock (in shares) Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Shares repurchased for tax withholdings on release of restricted stock Share-based Payment Arrangement, Decrease for Tax Withholding Obligation Conversion of preferred stock to common stock in connection with initial public offering (in shares) Stock Issued During Period, Shares, Conversion of Convertible Securities Conversion of preferred stock to common stock in connection with initial public offering Stock Issued During Period, Value, Conversion of Convertible Securities Issuance of common stock in connection with initial public offering and private placement, net of underwriters' discounts and commissions and issuance costs (in shares) Issuance of common stock in connection with initial public offering and private placement, net of underwriters' discounts and commissions and issuance costs Stock Issued During Period, Value, New Issues Exercise of stock options and awards (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Exercise of stock options and awards Stock Issued During Period, Value, Stock Options Exercised Assumed stock options in connection with acquisition Stock Issued During Period, Value, Acquisitions Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Net loss Shares outstanding, end of the period (in shares) Shareholders equity, ending balance Statement of Comprehensive Income [Abstract] Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Change in foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent Change in net unrealized gains (losses) on short-term investments Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Total other comprehensive income (loss), net of tax Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of Purchase Consideration Transferred Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Recognized Identified Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Schedule of Finite-Lived Intangible Assets Acquired and Estimated Useful Lives Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] Infrastructure Assets Acquired Under Finance Lease Agreements Assets Held under Finance Leases [Member] Assets Held under Finance Leases [Member] Infrastructure Assets Held under Capital Leases Assets Held under Capital Leases [Member] Accumulated depreciation Depreciation Depreciation Amortization expense Amortization of Intangible Assets Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract] Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract] Remaining three months of Fiscal 2019 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Total Finite-Lived Intangible Assets, Net Schedule of Goodwill Schedule of Goodwill [Table Text Block] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Line of Credit Line of Credit [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Letter of Credit Letter of Credit [Member] Lease, remaining lease term Lease, Remaining Lease Term Lease, Remaining Lease Term Lease, renewal term Lessee, Lease, Renewal Term Lessee, Lease, Renewal Term Operating sublease, term Lessee, Operating Sublease, Remaining Lease Term Lessee, Operating Sublease, Remaining Lease Term Sublease income Sublease Income Minimum obligations Operating Lease, Minimum Obligations Operating Lease, Minimum Obligations Tenant improvements Lessee, Operating Lease, Tenant Improvement Reimbursement Lessee, Operating Lease, Tenant Improvement Reimbursement Letter of credit Line of Credit Facility, Maximum Borrowing Capacity Tenant improvement allowance reimbursement Increase (Decrease) Tenant Improvement Allowance Reimbursement Increase (Decrease) Tenant Improvement Allowance Reimbursement Operating leases, not yet commenced, value Lessee, Operating Lease, Lease Not Yet Commenced, Amount Lessee, Operating Lease, Lease Not yet Commenced, Amount Operating leases, not yet commenced, term of contract Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract Intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Amortized cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract] Due within one year Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost Due between one to three years Debt Securities, Available For Sale Securities, Maturity, Allocated And Single Maturity Date, After One Through Four Years, Amortized Cost Available For Sale Securities, Debt Maturities After One Through Four Years, Amortized Cost Total Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost Estimated fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract] Due within one year Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Due between one to three years Debt Securities, Available For Sale Securities, Maturity, Allocated And Single Maturity Date, After One Through Four Years, Fair Value Available For Sale Securities, Debt Maturities After One Through Four Years, Fair Value Total Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value Non-income taxes payable Accrual for Taxes Other than Income Taxes, Current Accrued legal and other external fees Accrued Professional Fees, Current Deferred rent Accrued Rent, Current Other accrued and current liabilities Other Accrued Liabilities And Other Liabilities, Current Other Accrued Liabilities and Other Liabilities, Current Total accrued and other current liabilities Basis of presentation Basis of Accounting, Policy [Policy Text Block] Basis of consolidation Consolidation, Policy [Policy Text Block] Use of estimates Use of Estimates, Policy [Policy Text Block] Financial information about segments and geographic areas Segment Reporting, Policy [Policy Text Block] Foreign currency transactions Foreign Currency Transactions and Translations Policy [Policy Text Block] Revenue recognition and deferred commissions, net Revenue from Contract with Customer [Policy Text Block] Stock-based compensation Compensation Related Costs, Policy [Policy Text Block] Cash and cash equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Short-term investments Marketable Securities, Policy [Policy Text Block] Concentrations of credit risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Non-trade receivables Receivable [Policy Text Block] Property and equipment, net Property, Plant and Equipment, Policy [Policy Text Block] Lease obligations Lessee, Leases [Policy Text Block] Business combinations Business Combinations Policy [Policy Text Block] Long-lived assets, including goodwill and other acquired intangible assets, net Impairment or Disposal of Long-Lived Assets, Including Intangible Assets, Policy [Policy Text Block] Income taxes Income Tax, Policy [Policy Text Block] Fair value measurement Fair Value Measurement, Policy [Policy Text Block] Recently issued accounting pronouncements not yet adopted and Recently adopted accounting pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Net loss per share Earnings Per Share, Policy [Policy Text Block] Cash, Cash Equivalents and Short-Term Investments Cash, Cash Equivalents, and Short-term Investments [Text Block] Class A Class B Net loss attributable to common stockholders Weighted-average number of common shares outstanding used in computing basic and diluted net loss per common share (in shares) Net loss per common share, basic and diluted (in dollars per share) Geographic Areas Segment Reporting Disclosure [Text Block] Fair Value Measurements Fair Value Disclosures [Text Block] Number of shares available for issuance under the Plans Share-based Compensation Arrangement By Share-based Payment Award, Shares Available For Issuance [Roll Forward] Share-based Compensation Arrangement By Share-based Payment Award, Shares Available For Issuance [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Additional shares authorized (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Stock options assumed (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Assumed Through Business Acquisition Share-based Compensation Arrangement by Share-based Payment Award, Assumed Through Business Acquisition Options and RSUs canceled (in shares) Share-based Compensation Arrangement By Share-based Payment Award, Shares Canceled Share-based Compensation Arrangement By Share-based Payment Award, Shares Canceled Shares repurchased for tax withholdings on release of restricted stock (unaudited) (in shares) Restricted stock granted (in shares) Share-Based Compensation Arrangement By Share-based Payment Award, Decrease In Number of Shares Authorized From Stock Granted Share-Based Compensation Arrangement By Share-based Payment Award, Decrease In Number of Shares Authorized From Stock Granted Ending balance (in shares) Options Outstanding, Number of shares outstanding under the Plans Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Beginning balance (in shares) Stock options assumed (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed Through Business Acquisition Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed Through Business Acquisition Options exercised (in shares) Options canceled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares Ending balance (in shares) Vested during period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Unvested at end of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares Options Outstanding, Weighted- average exercise price per share Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Stock options assumed (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed In Business Acquisition, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed, Weighted Average Exercise Price Options exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Options canceled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Options granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Ending balance (in dollars per share) Vested during period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value Unvested at end of period (in dollars per shares) Options Outstanding, Weighted- average remaining contractual term (In years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Weighted-average contractual term Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Vested during period Share-based Compensation Arrangement By Share-based Payment Award, Options, Vested, Weighted Average Remaining Contractual Term Share-based Compensation Arrangement By Share-based Payment Award, Options, Vested, Weighted Average Remaining Contractual Term Options outstanding, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Vested during period, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Unvested during period, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Aggregate Intrinsic Value Restricted Stock Outstanding, Number of Plan shares outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number RSUs released (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Released in Period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Released in Period RSUs canceled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Restricted stock granted (in shares) Ending balance (in shares) Vested during period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Unvested at end of period (in shares) Restricted Stock Outstanding, Weighted- average grant date fair value per share Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value RSUs released (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Released in Period, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Released in Period, Weighted Average Grant Date Fair Value RSUs canceled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Shares repurchased for tax withholdings on release of restricted stock (in dollars per share) Shares Paid For Tax Withholding For Share Based Compensation, Weighted Average Grant Date Fair Value Shares Paid For Tax Withholding For Share Based Compensation, Weighted Average Grant Date Fair Value Restricted stock granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Ending balance (in dollars per share) Vested during period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Unvested at end of period (in dollars per share) Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Developed technology Developed Technology Rights [Member] Customer relationships Customer Relationships [Member] Software Computer Software, Intangible Asset [Member] Patents Patents [Member] Assembled workforce in asset acquisitions Assembled Workforce In Asset Acquisition [Member] Assembled Workforce In Asset Acquisition [Member] Licenses Licensing Agreements [Member] Trademarks and trade names Trademarks and Trade Names [Member] Other Other Intangible Assets [Member] Weighted Average Weighted Average [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Intangible assets, gross Intangible Assets, Gross (Excluding Goodwill) Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Intangible assets, net Weighted- average remaining useful life (In years) Finite-Lived Intangible Asset, Useful Life Intangible assets, retired Intangible Assets, Gross (Excluding Goodwill), Retired Intangible Assets, Gross (Excluding Goodwill), Retired Schedule of Cash and Cash Equivalents [Table] Schedule of Cash and Cash Equivalents [Table] Cash Cash [Member] Corporate notes and obligations Cash and Cash Equivalents [Line Items] Cash and Cash Equivalents [Line Items] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Short-term investments, amortized cost Debt Securities, Available-for-sale, Amortized Cost Short-term investments, unrealized gain Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Short-term investments, unrealized loss Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Short-term investments, estimated fair value Total cash, cash equivalents, and short term investments, before unrealized gains (losses) on investments Cash, Cash Equivalents, And Short Term Investments, Amortized Cost Cash, Cash Equivalents, And Short Term Investments, Amortized Cost Total cash, cash equivalents, and short term investments Cash, Cash Equivalents, and Short-term Investments Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Trade name Trade Names [Member] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Estimated fair values Finite-lived Intangible Assets Acquired Estimated weighted average useful lives (In years) Line of Credit Facility [Table] Line of Credit Facility [Table] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Credit And Guarantee Agreement Credit And Guarantee Agreement [Member] Credit And Guarantee Agreement [Member] Revolving Credit Facility Revolving Credit Facility [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] LIBOR London Interbank Offered Rate (LIBOR) [Member] Base Rate Base Rate [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Line of credit facility, maximum borrowing capacity Debt issuance fees Debt Issuance Costs, Line of Credit Arrangements, Gross Debt instrument, term Debt Instrument, Term Line of credit facility, accordion feature, increase limit Line Of Credit Facility, Accordion Feature, Increase Limit Line of Credit Facility, Accordion Feature, Increase Limit Unused capacity, commitment fee (percent) Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Commitment fee (percent) Line of Credit Facility, Commitment Fee Percentage Fronting fee (percent) Line Of Credit Facility, Fronting Fee Percentage Line Of Credit Facility, Fronting Fee Percentage Basis spread on variable rate (percent) Debt Instrument, Basis Spread on Variable Rate Covenant terms, minimum liquidity balance Line Of Credit Facility, Covenant Terms, Liquidity Ratio Required, Minimum Line Of Credit Facility, Covenant Terms, Liquidity Ratio Required, Minimum Aggregate letters of credit outstanding amount Letters of Credit Outstanding, Amount Remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Potentially Dilutive Securities Excluded from Computation of Earnings Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Weighted average grant date fair value of stock options assumed (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed in Period, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed in Period, Weighted Average Grant Date Fair Value Fair value of options assumed in business combination Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed Through Business Acquisition, Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed Through Business Acquisition, Fair Value Post combination, stock-based compensation expense Allocated Share-based Compensation Expense, Post Combination Allocated Share-based Compensation Expense, Post Combination Accrued and Other Current Liabilities Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] Operating leases Lessee, Operating Lease, Liability, Payment, Due [Abstract] 2019 (excluding the nine months ended September 30, 2019) Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total future minimum lease payments Lessee, Operating Lease, Liability, Payments, Due Less imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Less tenant improvement receivables Lessee, Operating Lease, Tenant Improvement Allowance Receivable Lessee, Operating Lease, Tenant Improvement Allowance Receivable Finance Lease, Liability, Payment, Due [Abstract] Finance Lease, Liability, Payment, Due [Abstract] 2019 (excluding the nine months ended September 30, 2019) Finance Lease, Liability, Payments, Remainder of Fiscal Year 2020 Finance Lease, Liability, Payments, Due Year Two 2021 Finance Lease, Liability, Payments, Due Year Three 2022 Finance Lease, Liability, Payments, Due Year Four 2023 Finance Lease, Liability, Payments, Due Year Five Thereafter Finance Lease, Liability, Payments, Due after Year Five Total future minimum lease payments Finance Lease, Liability, Payment, Due Less imputed interest Finance Lease, Liability, Undiscounted Excess Amount Less tenant improvement receivables Finance Lease, Tenant Improvement Allowance Receivable Finance Lease, Tenant Improvement Allowance Receivable Finance lease, liability Finance Lease, Liability Rent payments from sub-tenants Operating Lease, Lease Income, Lease Payments Rent payments from sub-tenants, term Operating Lease, Lease Income, Lease Payments, Term Operating Lease, Lease Income, Lease Payments, Term Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Statement of Cash Flows [Abstract] Cash flow from operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net loss to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Deprecation, Depletion And Amortization (Excluding Amortization Of Deferred Sales Commissions Deprecation, Depletion And Amortization (Excluding Amortization Of Deferred Sales Commissions Stock-based compensation Share-based Payment Arrangement, Noncash Expense Net gains on equity investments Other Other Noncash Income (Expense) Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Trade and other receivables, net Increase (Decrease) in Accounts and Other Receivables Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Other assets Increase (Decrease) in Other Operating Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued and other current liabilities Increase (Decrease) In Accrued Liabilities And Other Liabilities Increase (Decrease) In Accrued Liabilities and Other Liabilities Accrued compensation and benefits Increase (Decrease) in Employee Related Liabilities Deferred revenue Increase (Decrease) in Contract with Customer, Liability Other non-current liabilities Increase (Decrease) in Other Noncurrent Liabilities Tenant improvement allowance reimbursement Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flow from investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Capital expenditures Payments to Acquire Property, Plant, and Equipment Business combinations, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Purchases of short-term investments Payments to Acquire Debt Securities, Available-for-sale Proceeds from sales of short-term investments Proceeds from Sale of Short-term Investments Proceeds from maturities of short-term investments Proceeds from Maturities, Prepayments and Calls of Short-term Investments Other Payments for (Proceeds from) Other Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash flow from financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from initial public offering and private placement, net of underwriters' discounts and commissions Payments of deferred offering costs Shares repurchased for tax withholdings on release of restricted stock Payment, Tax Withholding, Share-based Payment Arrangement Proceeds from issuance of common stock, net of repurchases Proceeds from Issuance of Common Stock Principal payments on finance lease obligations Principal payments on finance lease obligations Repayments of Long-term Capital Lease Obligations Other Proceeds from (Payments for) Other Financing Activities Net cash (used in) provided by financing activities Net Cash Provided by (Used in) Financing Activities Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Change in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash and cash equivalents - beginning of period Cash and cash equivalents - end of period Supplemental cash flow data: Supplemental Cash Flow Information [Abstract] Property and equipment acquired under finance leases Property and equipment acquired under finance leases Lease Obligation Incurred