Investments, Fair Value Disclosure [Abstract] Investments in Marketable Securities Marketable Securities [Table Text Block] Share-based Payment Arrangement [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Stock Option Share-based Payment Arrangement, Option [Member] Number of Shares Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Expected term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Revenue from Contract with Customer [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Domain] Contract with Customer, Sales Channel [Domain] Desktop Desktop [Member] Desktop [Member] Mobile Mobile [Member] Mobile [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Revenues Revenue from Contract with Customer, Excluding Assessed Tax Revenues, percent Concentration Risk, Percentage Accounting Policies [Abstract] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Computer equipment and network hardware Computer Equipment [Member] Furniture, fixtures and office equipment Furniture and Fixtures [Member] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property, plant and equipment, useful life Property, Plant and Equipment, Useful Life Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Two Year RSUs Two Year RSUs [Member] Two Year RSUs [Member] Restricted awards Restricted awards [Member] Restricted awards including RSAs and RSUs Unvested restricted stock units Restricted Stock Units (RSUs) [Member] Equity plans other than ESPP Other Than ESPP [Member] Other Than ESPP [Member] Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Award vesting rights, percentage Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage RSUs granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Number of shares available for grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Evergreen annual % increase Evergreen Annual % Increase Evergreen Annual % Increase Quarterly Financial Information Disclosure [Abstract] Revenue Revenues Cost of revenue Cost of Revenue Sales and marketing Selling and Marketing Expense Technology and development Research and Development Expense General and administrative General and Administrative Expense Restructuring and other exit costs Restructuring Charges Total expenses Costs and Expenses Loss from operations Operating Income (Loss) Total other (income) expense, net Nonoperating Income (Expense) Loss before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision (benefit) for income taxes Income Tax Expense (Benefit) Net loss Net Income (Loss) Attributable to Parent Basic (usd per share) Earnings Per Share, Basic Diluted (usd per share) Earnings Per Share, Diluted Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Goodwill and Intangible Assets Disclosure [Abstract] Goodwill [Roll Forward] Goodwill [Roll Forward] Beginning balance Goodwill Additions from the acquisition of RTKio (Note 10) Goodwill, Acquired During Period Ending balance Payables and Accruals [Abstract] Schedule of Accounts Payable and Accrued Liabilities Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Restricted Stock Awards Restricted Stock [Member] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Canceled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Ending balance (in shares) Weighted-Average Grant Date Fair Value 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 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 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 Vested (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 Ending balance (in dollars per share) Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Business Combinations [Abstract] 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] RTK RTK.io [Member] RTK.io [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Purchase consideration Business Combination, Consideration Transferred Acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Cash acquired from acquisition Cash Acquired from Acquisition Working capital adjustment Business Combinations, Working Capital Adjustment Business Combinations, Working Capital Adjustment Statement of Financial Position [Abstract] Preferred stock, par or stated value per share (usd per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Preferred stock, shares outstanding Preferred Stock, Shares Outstanding Common stock, par or stated value per share Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares, issued Common Stock, Shares, Issued Common stock, shares, outstanding Common Stock, Shares, Outstanding Statement of Cash Flows [Abstract] OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net loss to net cash provided by (used in) operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Stock-based compensation Share-based Payment Arrangement, Noncash Expense Loss on disposal of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Provision for doubtful accounts Accounts Receivable, Credit Loss Expense (Reversal) Accretion of available for sale securities Accretion Of Available-For-Sale Securities Accretion Of Available-For-Sale Securities Non-cash lease expense Non-Cash Lease Expense Non-Cash Lease Expense Deferred income taxes Deferred Income Taxes and Tax Credits Unrealized foreign currency gains, net Foreign Currency Transaction Gain (Loss), Unrealized Changes in operating assets and liabilities, net of effect of business acquisitions: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities Other liabilities Increase (Decrease) in Other Operating Liabilities Net cash provided by (used in) operating activities Net Cash Provided by (Used in) Operating Activities INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Capitalized internal use software development costs Payments to Develop Software Acquisitions, net of cash acquired Investments in available-for-sale securities Payments to Acquire Debt Securities, Available-for-sale Maturities of available-for-sale securities Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Sales of available-for-sale securities Proceeds from Sale of Debt Securities, Available-for-sale Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Proceeds from exercise of stock options Proceeds from Stock Options Exercised Proceeds from issuance of common stock under employee stock purchase plan Proceeds, Issuance of Shares, Share-based Payment Arrangement, Including Option Exercised Taxes paid related to net share settlement Payment, Tax Withholding, Share-based Payment Arrangement Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities EFFECT OF EXCHANGE RATE CHANGES ON CASH, CASH EQUIVALENTS AND RESTRICTED CASH Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect CASH, CASH EQUIVALENTS AND RESTRICTED CASH — Beginning of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents CASH, CASH EQUIVALENTS AND RESTRICTED CASH — End of period SUPPLEMENTAL DISCLOSURES OF OTHER CASH FLOW INFORMATION: Supplemental Cash Flow Information [Abstract] Cash paid for income taxes Income Taxes Paid, Net Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activities Capitalized assets financed by accounts payable and accrued expenses Capital Expenditures Incurred but Not yet Paid Capitalized stock-based compensation Share-based Payment Arrangement, Amount Capitalized Operating lease right-of-use assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Research and Development [Abstract] Schedule Of Internal Use Software Costs Schedule Of Internal Use Software Costs [Table Text Block] Schedule of Internal Use Software Costs [Table Text Block] Income Tax Disclosure [Abstract] Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Foreign Current Foreign Tax Expense (Benefit) Total current provision Current Income Tax Expense (Benefit) Deferred: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Foreign Deferred Foreign Income Tax Expense (Benefit) Total deferred benefit Deferred Income Tax Expense (Benefit) Total provision (benefit) for income taxes Equity [Abstract] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Other Commitments [Table] Other Commitments [Table] Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Financial Standby Letter of Credit Financial Standby Letter of Credit [Member] Lease Arrangements [Axis] Lease Arrangements [Axis] Lease Arrangements [Axis] Lease Arrangements [Domain] Lease Arrangements [Domain] [Domain] for Lease Arrangements [Axis] Office Lease Office Lease [Member] Office Lease [Member] Other Commitments [Line Items] Other Commitments [Line Items] 2020 Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months Letters of credit outstanding, amount Letters of Credit Outstanding, Amount 2021 Lessee, Operating Lease, Liability, Payments, Due Year Two 2022 Lessee, Operating Lease, Liability, Payments, Due Year Three 2023 Lessee, Operating Lease, Liability, Payments, Due Year Four 2024 Lessee, Operating Lease, Liability, Payments, Due Year Five Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Restructuring and Related Activities [Abstract] Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Restructuring Plan [Axis] Restructuring Plan [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] The 2018 Restructuring Events The 2018 Restructuring Events [Member] The 2018 Restructuring Events [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Accrued restructuring costs Restructuring Reserve Leases [Abstract] Leases Lessee, Operating Leases [Text Block] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Accumulated Deficit Retained Earnings [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning Balance (in shares) Beginning Balance Stockholders' Equity Attributable to Parent Exercise of common stock options (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Exercise of common stock options Stock Issued During Period, Value, Stock Options Exercised Restricted stock awards, net (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Restricted stock awards, net Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Issuance of common stock related to employee stock purchase plan (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Issuance of common stock related to employee stock purchase plan Stock Issued During Period, Value, Employee Stock Purchase Plan Issuance of common stock related to RSU vesting (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Issuance of common stock related to RSU vesting Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Shares withheld related to net share settlement (in shares) Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Shares withheld related to net share settlement Share-based Payment Arrangement, Decrease for Tax Withholding Obligation Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Ending Balance (in shares) Ending Balance Accounts Payable and Accrued Expense Accounts Payable and Accrued Liabilities Disclosure [Text Block] Basis of Consolidation Basis of Accounting, Policy [Policy Text Block] Segments Segment Reporting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Revenue Recognition Revenue [Policy Text Block] Cost of Revenue Cost of Goods and Service [Policy Text Block] Sales and Marketing Sales and Marketing [Policy Text Block] Sales and Marketing [Policy Text Block] Technology and Development Research, Development, and Computer Software, Policy [Policy Text Block] General and Administrative Selling, General and Administrative Expenses, Policy [Policy Text Block] Restructuring and Other Exit Costs Costs Associated with Exit or Disposal Activities or Restructurings, Policy [Policy Text Block] Stock-Based Compensation Share-based Payment Arrangement [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Capital Stock Stockholders' Equity, Policy [Policy Text Block] Net Income (Loss) Per Share Attributable to Common Stockholders Earnings Per Share, Policy [Policy Text Block] Comprehensive Income (Loss) Comprehensive Income, Policy [Policy Text Block] Cash, Cash Equivalents, and Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Marketable Securities Marketable Securities, Policy [Policy Text Block] Accounts Receivable Allowance for Doubtful Accounts Receivables, Trade and Other Accounts Receivable, Allowance for Doubtful Accounts, Policy [Policy Text Block] Property and Equipment, Net Property, Plant and Equipment, Policy [Policy Text Block] Internal Use Software Development Costs Internal Use Software, Policy [Policy Text Block] Intangible Assets Intangible Assets, Finite-Lived, Policy [Policy Text Block] Impairment of Long-Lived Assets including Internal Use Capitalized Software Costs Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Business Combinations Business Combinations Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Operating and Finance Leases Lessee, Leases [Policy Text Block] Fair Value of Financial Instruments Fair Value Measurement, Policy [Policy Text Block] Concentration of Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Foreign Currency Transactions and Translation Foreign Currency Transactions and Translations Policy [Policy Text Block] Recently Adopted Accounting Pronouncements and Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Debt Disclosure [Abstract] Line of Credit Facility [Table] Line of Credit Facility [Table] Debt Instrument Covenant Compliance Period [Axis] Debt Instrument Covenant Compliance Period [Axis] Debt Instrument Covenant Compliance Period [Axis] Debt Instrument Covenant Compliance Period [Domain] Debt Instrument Covenant Compliance Period [Domain] [Domain] for Debt Instrument Covenant Compliance Period [Axis] Covenant Compliance Period Two Covenant Compliance Period Two [Member] Covenant Compliance Period Two [Member] Covenant Compliance Period Three Covenant Compliance Period Three [Member] Covenant Compliance Period Three [Member] Debt Covenant Terms [Axis] Debt Covenant Terms [Axis] Debt Covenant Terms [Axis] Debt Covenant Terms [Domain] Debt Covenant Terms [Domain] [Domain] for Debt Covenant Terms [Axis] Covenant Term, Scenario One Covenant Term, Scenario One [Member] Covenant Term, Scenario One [Member] Covenant Term, Scenario Two Covenant Term, Scenario Two [Member] Covenant Term, Scenario Two [Member] Streamline Period [Axis] Debt Instrument Covenant Compliance Streamline Period [Axis] Debt Instrument Covenant Compliance Streamline Period [Axis] Streamline Period [Domain] DebtInstrumentCovenantComplianceStreamlinePeriodAxis [Domain] [Domain] for DebtInstrumentCovenantComplianceStreamlinePeriod [Axis] Streamline Period Applies Streamline Period Applies [Member] Streamline Period Applies [Member] Streamline Period Does Not Apply Streamline Period Does Not Apply [Member] Streamline Period Does Not Apply [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Credit Facility Revolving Credit Facility [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 2011 Loan Agreement 2011 Loan Agreement [Member] 2011 Loan Agreement [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] London Interbank Offered Rate (LIBOR) London Interbank Offered Rate (LIBOR) [Member] Prime Rate Prime Rate [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Line of credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Line of credit facility, remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Debt issuance costs, net Debt Issuance Costs, Net Line of credit facility, unused capacity, commitment fee percentage Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Debt instrument, basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Debt instrument adjusted quick ratio requirement in streamline period Debt Instrument Adjusted Quick Ratio Requirement In Streamline Period Debt Instrument Adjusted Quick Ratio Requirement In Streamline Period Debt instrument adjusted quick ratio requirement Debt Instrument Adjusted Quick Ratio Requirement Debt Instrument Adjusted Quick Ratio Requirement Debt instrument covenant compliance adjusted earnings before interest taxes depreciation and amortization maximum Debt Instrument Covenant Compliance Adjusted Earnings Before Interest Taxes Depreciation And Amortization Maximum Debt Instrument Covenant Compliance Adjusted Earnings Before Interest Taxes Depreciation And Amortization Maximum Debt instrument, covenant compliance, adjusted earnings before interest taxes depreciation and amortization minimum Debt Instrument, Covenant Compliance, Adjusted Earnings Before Interest Taxes Depreciation And Amortization Minimum Debt Instrument, Covenant Compliance, Adjusted Earnings Before Interest Taxes Depreciation And Amortization Minimum Debt instrument adjusted quick ratio Debt Instrument Adjusted Quick Ratio Debt Instrument Adjusted Quick Ratio Adjusted EBITDA threshold Adjusted EBITDA Threshold Adjusted EBITDA Threshold Operating lease expense Operating Expenses [Abstract] 2019 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2020 Operating Leases, Future Minimum Payments, Due in Two Years 2021 Operating Leases, Future Minimum Payments, Due in Three Years 2022 Operating Leases, Future Minimum Payments, Due in Four Years 2023 Operating Leases, Future Minimum Payments, Due in Five Years Total Operating Leases, Future Minimum Payments Due Operating sublease income Lessee, Operating Sublease, Description [Abstract] 2019 Operating Leases Rent Expense Sublease Rentals Due in Next Twelve Months Operating Leases Rent Expense Sublease Rentals Due in Next Twelve Months 2020 Operating Leases Rent Expense Sublease Rentals Due in Two Years Operating Leases Rent Expense Sublease Rentals Due in Two Years 2021 Operating Leases Rent Expense Sublease Rentals Due in Three Years Operating Leases Rent Expense Sublease Rentals Due in Three Years 2022 Operating Leases Rent Expense Sublease Rentals Due in Four Years Operating Leases Rent Expense Sublease Rentals Due in Four Years 2023 Operating Leases Rent Expense Sublease Rentals Due in Five Years Operating Leases Rent Expense Sublease Rentals Due in Five Years Total Operating Leases, Rent Expense, Sublease Rentals Due Operating Leases, Rent Expense, Sublease Rentals Due Total Lessee, Operating Lease, Liability, Payment, Due [Abstract] 2019 Operating Leases Rent Expense Net In Next Twelve Months Operating Leases Rent Expense Net In Next Twelve Months 2020 Operating Leases Rent Expense Net, in Two Years Operating Leases Rent Expense Net, in Two Years 2021 Operating Leases Rent Expense Net, in Three Years Operating Leases Rent Expense Net, in Three Years 2022 Operating Leases Rent Expense Net, in Four Years Operating Leases Rent Expense Net, in Four Years 2023 Operating Leases Rent Expense Net, in Five Years Operating Leases Rent Expense Net, in Five Years Total Operating Leases, Rent Expense, Net Due Operating Leases, Rent Expense, Net Due Earnings Per Share [Abstract] Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Property, Plant and Equipment [Abstract] Depreciation expense on property and equipment Depreciation Impairment of long-lived assets Impairment of Long-Lived Assets Held-for-use Right of use lease asset Operating Lease, Right-of-Use Asset Property and equipment under finance leases Finance Lease, Right-of-Use Asset Property and equipment under capital leases Capital Leased Assets, Gross Debt Debt and Capital Leases Disclosures [Text Block] Schedule of Income before Income Tax, Domestic and Foreign Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns Roll Forward Schedule of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns Roll Forward [Table Text Block] Deferred Tax Assets: Deferred Tax Assets, Net of Valuation Allowance [Abstract] Accrued liabilities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Stock-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Net operating loss carryovers Deferred Tax Assets, Operating Loss Carryforwards Tax credit carryovers Deferred Tax Assets, Tax Credit Carryforwards, Research Other Deferred Tax Assets, Other Total deferred tax assets Deferred Tax Assets, Gross Less valuation allowance Deferred Tax Assets, Valuation Allowance Deferred tax assets, net of valuation allowance Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Liabilities: Deferred Tax Liabilities, Gross [Abstract] Fixed assets Deferred Tax Liabilities, Property, Plant and Equipment Intangible assets Deferred Tax Liabilities, Goodwill and Intangible Assets Total deferred tax liabilities Deferred Tax Liabilities, Gross Net deferred tax assets (liability) Deferred Tax Assets, Net Fair Value Disclosures [Abstract] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Cash equivalents Money Market Funds [Member] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Recurring Fair Value, Recurring [Member] 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] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Unvested restricted stock awards Restricted Stock Units (RSUs) Fair value of restricted stock Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Unrecognized employee stock-based compensation Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Unrecognized employee stock-based compensation, period for recognition Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Intrinsic value of nonvested unit Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested Accounts payable—seller Accounts Payable, Seller, Current Description of balance sheet netting of assets and liabilities per ASC 210-20. Accounts payable—trade Accounts Payable, Trade, Current Accrued employee-related payables Employee-related Liabilities, Current Total Accounts Payable and Accrued Liabilities, Current Net Income (Loss) Per Share Earnings Per Share [Text Block] Schedule of Business Acquisitions, by Acquisition Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Finite-lived Intangible Assets Acquired as Part of Business Combination Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] Basic and Diluted EPS: Earnings Per Share, Basic [Abstract] Net loss Weighted-average common shares outstanding Weighted Average Number Of Shares Outstanding Including Unvested Restricted Shares, Basic and Diluted Weighted Average Number Of Shares Outstanding Including Unvested Restricted Shares, Basic and Diluted Weighted-average unvested restricted shares Weighted Average Number of Shares, Restricted Stock Weighted-average common shares outstanding used to compute net loss per share Weighted Average Number Of Shares Outstanding Used To Compute Earnings Per Share, Basic And Diluted Weighted Average Number Of Shares Outstanding Used To Compute Earnings Per Share, Basic And Diluted Basic and diluted net loss per share (usd per share) Earnings Per Share, Basic and Diluted U.S. federal statutory income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent State income taxes, net of federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Foreign income (loss) at other than U.S. rates Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Stock-based compensation expense Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent Meals and entertainment Effective Income Tax Rate Reconciliation, Nondeductible Expense, Meals and Entertainment, Percent Debt cancellation Effective Income Tax Rate Reconciliation, Intercompany Financing Charges Effective Income Tax Rate Reconciliation, Intercompany Financing Charges Other permanent items Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Sec 162(m) officers compensation Effective Income Tax Rate Reconciliation, Officers Compensation, Percent Effective Income Tax Rate Reconciliation, Officers Compensation, Percent Provision to return adjustments Effective Income Tax Rate Reconciliation, Return Adjustment Provision Effective Income Tax Rate Reconciliation, Return Adjustment Provision Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Accumulated Other Comprehensive Loss Comprehensive Income (Loss) Note [Text Block] Payment terms Revenue, Payment Terms Revenue, Payment Terms Internal use software development costs, gross Capitalized Computer Software, Gross Accumulated amortization Capitalized Computer Software, Accumulated Amortization Internal use software development costs, net Capitalized Computer Software, Net Schedules of Maturity of Lease Liabilities Lessee, Operating Lease, Liability, Maturity [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Finite-Lived Intangible Assets Acquired as Part of Business Combination [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] Non-compete agreements Noncompete Agreements [Member] Trademark & trade name Trademarks and Trade Names [Member] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Finite-lived intangible assets acquired Finite-lived Intangible Assets Acquired Estimated Useful Life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Internal Use Software Development Costs Research, Development, and Computer Software Disclosure [Text Block] Intrinsic values of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Unrecognized employee stock-based compensation Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Weighted average grant date fair value (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Fair value of options vested in period Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Capitalized computer software, additions Capitalized Computer Software, Additions Capitalized computer software, amortization Capitalized Computer Software, Amortization Internal use software development costs, write-offs Internal Use Software Development Costs, Write-offs Internal Use Software Development Costs, Write-offs Estimated amortization expense, 2020 Capitalized Computer Software, Amortization Expense, Next Twelve Months Capitalized Computer Software, Amortization Expense, Next Twelve Months Estimated amortization expense, 2021 Capitalized Computer Software, Amortization Expense, Year Two Capitalized Computer Software, Amortization Expense, Year Two Estimated amortization expense, 2022 Capitalized Computer Software, Amortization Expense, Year Three Capitalized Computer Software, Amortization Expense, Year Three Estimated amortization expense, 2023 Capitalized Computer Software, Amortization Expense, Year Four Capitalized Computer Software, Amortization Expense, Year Four Capitalized computer software impairments Capitalized Computer Software, Impairments Beginning balance Unrecognized Tax Benefits Increases related to prior year tax positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Decreases related to prior year tax positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Increases related to current year tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Decreases related to current year tax positions Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions Ending balance Restructuring and Other Exit Costs Restructuring and Related Activities Disclosure [Text Block] Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Finite-lived Intangible Assets Amortization Finite-lived Intangible Assets 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Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Unrealized gain on investments Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent Other comprehensive income (loss) Quarterly Financial Data (Unaudited) Quarterly Financial Information [Table Text Block] Number of operating segments Number of Operating Segments Concentration Risk [Table] Concentration Risk [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] Measurement Input Type [Axis] Measurement Input Type [Axis] Measurement Input Type [Domain] Measurement Input Type [Domain] Measurement input, expected dividend payment Measurement Input, Expected Dividend Payment [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Customer one Customer One [Member] Customer One [Member] Customer two Customer Two [Member] Customer Two [Member] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Customer concentration risk, accounts receivable Customer Concentration Risk [Member] Concentration Risk [Line Items] Concentration Risk [Line Items] Alternative investment, measurement input Alternative Investment, Measurement Input Lease liabilities—total (discounted) Operating Lease, Liability Share-based compensation arrangement by share-based payment award, award requisite service period Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period Share-based compensation arrangement by share-based payment award, number of shares authorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Restricted cash Restricted Cash Accounts receivable, allowance for credit loss Accounts Receivable, Allowance for Credit Loss Accounts receivable, allowance for credit loss, writeoff Accounts Receivable, Allowance for Credit Loss, Writeoff Fiscal Year Total lease payments (undiscounted) Lessee, Operating Lease, Liability, Payments, Due Less: imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Schedule of Share-based Compensation, Stock Options, Activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Nonvested Restricted Stock Shares Activity Nonvested Restricted Stock Shares Activity [Table Text Block] Schedule of Nonvested Restricted Stock Units Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs for all Plans Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Fair Value Measurements Fair Value Disclosures [Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Investment Type [Axis] Investment Type [Axis] Investments [Domain] Investments [Domain] Available-for-sale—short-term Short-term Investments [Member] U.S. Treasury, government and agency debt securities US Treasury and Government [Member] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Amortized Cost Debt Securities, Available-for-sale, Amortized Cost Gross Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Fair Value Debt Securities, Available-for-sale Income Statement [Abstract] Expenses: Costs and Expenses [Abstract] Total expenses Loss from operations Other (income) expense: Nonoperating Income (Expense) [Abstract] Interest income, net Interest Income (Expense), Net Other income Other Operating Income Foreign exchange (gain) loss, net Foreign Currency Transaction Gain (Loss), before Tax Total other (income) expense, net Loss before income taxes Net loss Net loss per share: Basic and Diluted (usd per share) Weighted average shares used to compute net loss per share: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic and Diluted (in shares) Quarterly Financial Data (Unaudited) Quarterly Financial Information [Text Block] Investments Investment Holdings, Schedule of Investments [Text Block] Revenues Revenue from Contract with Customer [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Nature of Operations Nature of Operations [Text Block] Stock-Based Compensation Share-based Payment Arrangement [Text Block] Schedule of Goodwill Schedule of Goodwill [Table Text Block] Schedule of Finite-Lived Intangible Assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Amortization expense of intangible assets Amortization of Intangible Assets Historical cost Impairment of Intangible Assets, Finite-lived Purchased software Computer Software, Intangible Asset [Member] Leasehold improvements Leasehold Improvements [Member] Domestic Plan Domestic Plan [Member] International Non-US [Member] Gross property and equipment Property, Plant and Equipment, Gross Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, net Property, Plant and Equipment, Net Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Client relationships Other intangible assets Other Intangible Assets [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Asset, Useful Life Finite-Lived Intangible Asset, Useful Life Cover page. Document Type Document Type Document Annual Report Document Annual 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 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, Address Line Two Entity Address, Address Line Two 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 Well-known Seasoned Issuer Entity Well-known Seasoned Issuer 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Hierarchy and NAV [Domain] Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Available-for-sale securities Organization and Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Gross Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Gross Expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning balance (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised (usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Expired (usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Forfeited (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value Ending balance (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Outstanding, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Exercisable (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Exercisable (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Exercisable, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Lease Arrangement, Type [Axis] Lease Arrangement, Type [Axis] Lease Arrangement, Type [Domain] Lease Arrangement, Type [Domain] Data Centers For Cloud-Based Services Data Centers For Cloud-Based Services [Member] Data Centers For Cloud-Based Services [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Lease renewal term Lessee, Operating Lease, Renewal Term Term of lease contract Lessee, Operating Lease, Term of Contract Remaining lease term Operating Lease, Weighted Average Remaining Lease Term Discount rate Operating Lease, Weighted Average Discount Rate, Percent Operating lease expense Operating Lease, Expense Expense Lease, Cost Short-term lease cost Short-term Lease, Cost Rent expense, net Operating Leases, Rent Expense, Net Rent expense Operating Leases, Rent Expense Sublease Income Sublease Income Fair Value, Assets Measured on Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2014 Employee Stock Purchase Plan 2014 Employee Stock Purchase Plan [Member] 2014 Employee Stock Purchase Plan [Member] Employee Stock Employee Stock [Member] Maximum employee subscription rate Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate Purchase price of common stock, percent Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Number of shares reserved 2020 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2024 Finite-Lived Intangible Assets, Amortization Expense, Year Five Total Finite-Lived Intangible Assets, Net ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Marketable securities Marketable Securities Accounts receivable, 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 Property and equipment, net Internal use software development costs, net Internal Use Software Development Costs, Net The carrying amount of internal use software development costs net of accumulated amortization as of the balance sheet date. Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Goodwill Other assets, non-current Other Assets, Noncurrent TOTAL ASSETS Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] LIABILITIES Liabilities [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable and accrued expenses Lease liabilities - current portion Operating Lease, Liability, Current Other current liabilities Other Liabilities, Current TOTAL CURRENT LIABILITIES Liabilities, Current Lease liabilities - non-current portion Operating Lease, Liability, Noncurrent Other liabilities, non-current Other Liabilities, Noncurrent TOTAL LIABILITIES Liabilities Commitments and contingencies (Note 17) Commitments and Contingencies STOCKHOLDERS' EQUITY Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.00001 par value, 10,000 shares authorized at December 31, 2019 and December 31, 2018; 0 shares issued and outstanding at December 31, 2019 and December 31, 2018 Preferred Stock, Value, Issued Common stock, $0.00001 par value; 500,000 shares authorized at December 31, 2019 and December 31, 2018; 53,888 and 51,159 shares issued, and outstanding at December 31, 2019 and December 31, 2018, respectively Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated deficit Retained Earnings (Accumulated Deficit) TOTAL STOCKHOLDERS' EQUITY TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of revenue Cost of Sales [Member] Sales and marketing Selling and Marketing Expense [Member] Technology and development Research and Development Expense [Member] General and administrative General and Administrative Expense [Member] Restructuring and other exit costs Restructuring Charges [Member] Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Stock-based compensation expense Share-based Payment Arrangement, Expense Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Developed technology Trademarks Trademarks [Member] Amortizable intangible assets: Finite-Lived Intangible Assets, Gross Accumulated amortization—intangible assets: Finite-Lived Intangible Assets, Accumulated Amortization Domestic Income (Loss) from Continuing Operations before Income Taxes, Domestic International Income (Loss) from Continuing Operations before Income Taxes, Foreign Loss before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] Research Tax Credit Carryforward Research Tax Credit Carryforward [Member] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Domestic Tax Authority Domestic Tax Authority [Member] State and Local Jurisdiction State and Local Jurisdiction [Member] Foreign Tax Authority Foreign Tax Authority [Member] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Income Tax Authority, Name [Domain] Tax Period [Axis] Tax Period [Axis] Tax Period [Domain] Tax Period [Domain] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Change in valuation allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Operating loss carryforwards Operating Loss Carryforwards Tax credit carryforwards Tax Credit Carryforward, Amount Unremitted earnings of the subsidiaries outside of the United States Undistributed Earnings of Foreign Subsidiaries Tax cuts and jobs act, incomplete accounting, transition tax for accumulated foreign earnings, provisional income tax expense Tax Cuts and Jobs Act, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense Statement of Comprehensive Income [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Other comprehensive income (loss) Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent 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] Options to purchase common stock Equity Option [Member] ESPP Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Total shares excluded from net income (loss) per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Prepaid and other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Total assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Accounts payable and accrued expenses Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities Deferred tax liability, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Total liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Total net assets acquired Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net