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Performance awards Performance Shares [Member] Shares issuable pursuant to the ESPP Employee Stock [Member] Anti-dilutive securities Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Total common stock equivalents (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Goodwill and Intangible Assets Disclosure [Abstract] Amortization expense of intangible assets Amortization of Intangible Assets Restructuring and Related Activities [Abstract] Restructuring Charges Restructuring and Related Activities Disclosure [Text Block] Net Loss Per Common Share Earnings Per Share [Text Block] Convertible Promissory Note Receivable Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 3 Fair Value, Inputs, Level 3 [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] Total assets measured at fair value Assets, Fair Value Disclosure, Recurring Liabilities measured at fair value Liabilities, Fair Value Disclosure, Recurring Business Combinations [Abstract] Allocation of estimated fair values of net assets acquired Business Combination, Separately Recognized Transactions [Table Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of revenue—Other Cost of Sales [Member] Cost of revenue—Ticketing service Service And Processing Costs [Member] Service And Processing Costs [Member] Product development Research and Development Expense [Member] Sales and marketing Selling and Marketing Expense [Member] General and administrative General and Administrative Expense [Member] Stock-based compensation expenses: Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] Total stock-based compensation expense Allocated Share-based Compensation Expense Temporary Equity Disclosure [Abstract] Temporary Equity, by Class of Stock [Table] Temporary Equity, by Class of Stock [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Series A convertible preferred stock Series A Preferred Stock [Member] Sale of Stock [Axis] Sale of Stock [Axis] Sale of Stock [Domain] Sale of Stock [Domain] Initial closing Initial Closing [Member] Initial Closing [Member] Second closing Closing Upon Certain Regulatory Approvals [Member] Closing Upon Certain Regulatory Approvals [Member] Temporary Equity [Line Items] Temporary Equity [Line Items] Agreement to sell shares (in shares) Temporary Equity, Share Subscriptions Share price (in dollars per share) Shares Issued, Price Per Share Agreement to sell shares Temporary Equity, Shares Subscribed but Unissued, Subscriptions Receivable Payments of issuance costs Payments of Stock Issuance Costs Proceeds from issuance of redeemable convertible preferred stock Proceeds from Issuance of Convertible Preferred Stock Income Tax Disclosure [Abstract] Valuation Allowance [Table] Valuation Allowance [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] AdsWizz AdsWizz, Inc. [Member] AdsWizz, Inc. [Member] Valuation Allowance [Line Items] Valuation Allowance [Line Items] Release of valuation allowance Valuation Allowances and Reserves, Period Increase (Decrease), Acquisitions Valuation Allowances and Reserves, Period Increase (Decrease), Acquisitions Revenue from Contract with Customer [Abstract] Revenues Revenue from Contract with Customer [Text Block] Schedule of redeemable convertible preferred stock Schedule of Stock by Class [Table Text Block] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Line of credit Line of Credit [Member] Letter of credit Letter of Credit [Member] Maximum borrowings available Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Option To Increase Maximum Borrowing Capacity Line of Credit Facility, Option To Increase Maximum Borrowing Capacity Line of Credit Facility, Option To Increase Maximum Borrowing Capacity Outstanding amount Letters of Credit Outstanding, Amount Outstanding borrowings Long-term Line of Credit Available borrowing capacity Line of Credit Facility, Current Borrowing Capacity Discontinued Operations and Disposal Groups [Abstract] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Sold Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Group Name [Domain] Disposal Group Name [Domain] Ticketfly Ticketfly, Inc. [Member] Ticketfly, Inc. [Member] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Aggregate unadjusted purchase price Disposal Group, Including Discontinued Operation, Consideration Cash portion of purchase price Disposal Group, Including Discontinued Operation, Consideration, Cash Disposal Group, Including Discontinued Operation, Consideration, Cash Convertible subordinated promissory note Disposal Group, Including Discontinued Operation, Consideration, Notes Receivable Disposal Group, Including Discontinued Operation, Consideration, Notes Receivable Unamortized discount Receivable with Imputed Interest, Discount Costs to sell Business Acquisition, Transaction Costs Working capital and certain indemnification provisions adjustments Disposal Group, Including Discontinued Operation, Consideration Adjustments, Working Capital Disposal Group, Including Discontinued Operation, Consideration Adjustments, Working Capital Net purchase price Disposal Group, Including Discontinued Operation, Net Purchase Price Disposal Group, Including Discontinued Operation, Net Purchase Price Cancellation fee Notes Receivable Cancellation Fee Notes Receivable Cancellation Fee Loss on sale Gain (Loss) on Cancellation of Notes Receivable Gain (Loss) on Cancellation of Notes Receivable Accounting Policies [Abstract] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Consolidation Consolidation, Policy [Policy Text Block] Reclassification Reclassification, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Business Combinations, Goodwill and Intangible Assets, net Business Combinations Policy [Policy Text Block] Concentration of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Commitments and Contingencies Commitments and Contingencies, Policy [Policy Text Block] Schedule of assumptions used for determining the per-share fair value of shares granted under the ESPP Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block] Schedule of stock-based compensation expenses related to all employee and non-employee stock-based awards Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] 1.75% convertible senior notes due 2020 Debt Instrument [Line Items] Debt Instrument [Line Items] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Remainder of 2018 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Net Carrying Value Finite-Lived Intangible Assets, Net Schedule of Acquired Indefinite-lived Intangible Assets by Major Class [Table] Schedule of Acquired Indefinite-lived Intangible Assets by Major Class [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Acquired Indefinite-lived Intangible Assets [Line Items] Acquired Indefinite-lived Intangible Assets [Line Items] Estimated useful life in years Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Organization, Consolidation and Presentation of Financial Statements [Abstract] Description of Business and Basis of Presentation Business Description and Basis of Presentation [Text Block] Quoted Prices in Active Markets for Identical Instruments (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Investment Type [Axis] Investment Type [Axis] Investments [Domain] Investments [Domain] Money market funds Money Market Funds [Member] Commercial paper Commercial Paper [Member] Corporate debt securities Corporate Debt Securities [Member] Assets Assets, Fair Value Disclosure [Abstract] Total assets measured at fair value Number of owned securities that were in an unrealized loss position Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions 1.75% convertible senior notes due 2023 Convertible Senior Notes Due 2023 [Member] Convertible Senior Notes Due 2023 [Member] 1.75% convertible senior notes Long-term Debt, Gross Unamortized discount and deferred issuance costs Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Long-term debt, net Long-term Debt 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] Equity Award [Domain] Equity Award [Domain] ESPP Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Percentage of eligible compensation to purchase common stock through payroll deductions (as a percent) Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate Offering period Share-Based Compensation Arrangement By Share-Based Payment Award, Offering Period Represents the offering period for award under the share based compensation. Contributions from employees withheld Share Based Compensation Arrangement by Share Based Payment Award Contribution from Employees Withheld Represents the amount of contributions from employees withheld. 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Stock options Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Expected life (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 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 Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected volatility, minimum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Expected volatility, maximum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Income Taxes Income Tax Disclosure [Text Block] Long-term debt, net Share price (in dollars per share) Share Price 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] 2018 Reduction in Force 2018 Reduction in Force [Member] 2018 Reduction in Force [Member] 2017 Reduction in Force 2017 Reduction in Force [Member] 2017 Reduction in Force [Member] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Employee severance and benefits costs Employee Severance [Member] Restructuring Cost and Reserve [Line Items] 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Gross Profit Operating expenses Operating Expenses [Abstract] Product development Research and Development Expense (Excluding Acquired in Process Cost) Sales and marketing Selling and Marketing Expense General and administrative General and Administrative Expense Goodwill impairment Goodwill, Impairment Loss Contract termination fees Gain (Loss) on Contract Termination Total operating expenses Operating Expenses Loss from operations Operating Income (Loss) Interest expense Interest Expense Other income, net Other Nonoperating Income Total other expense, net Other Nonoperating Income (Expense) Loss before provision for income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest (Provision for) benefit from income taxes Income Tax Expense (Benefit) Net loss Net Income (Loss) Attributable to Parent Net loss available to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Basic and diluted net loss per common share (in dollars per share) Earnings Per Share, Basic and Diluted Weighted-average basic and diluted common shares Weighted Average Number of Shares Outstanding, Basic and Diluted Contract duration Contract Duration Contract Duration Maximum payment term Maximum Payment Term Maximum Payment Term Revenue from External Customers by Products and Services [Table] Revenue from External Customers by Products and Services [Table] Revenue from External Customer [Line Items] Revenue from External Customer [Line Items] Subscription payment term Subscription Payment Term Subscription Payment Term Revenues recognized, previously included deferred revenue Contract with Customer, Liability, Revenue Recognized Note term Notes Issued, Term Notes Issued, Term Stated interest rate Receivable, Interest Rate, Stated Percentage Receivable, Interest Rate, Stated Percentage Convertible promissory note receivable Receivable with Imputed Interest, Net Amount Purchase price adjustments Receivable with Imputed Interest, Purchase Price Adjustments Receivable with Imputed Interest, Purchase Price Adjustments Interest receivable Interest Receivable Stock-based Compensation Plans and Awards Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Investment Holdings [Table] Investment Holdings [Table] Cash Cash [Member] Commercial paper, cash and cash equivalents Commercial paper, short-term investments Commercial Paper, Not Included with Cash and Cash Equivalents [Member] Cash, Cash Equivalents and Investments Investment Holdings [Line Items] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Short-term investments Short-term Investments Cash, cash equivalents and investments Cash, Cash Equivalents, and Short-term Investments Schedule of the computation of historical basic and diluted net loss per share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of potential common shares outstanding excluded from the computation of diluted net loss per share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Total finite-lived intangible assets Finite-Lived Intangible Assets, Major Class Name [Domain] Developed technology Developed Technology [Member] Developed Technology [Member] Customer relationships Customer Relationships [Member] Trade name Trade Name [Member] Trade Name [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Finite-lived intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Tangible assets acquired, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Deferred tax liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent Net assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Goodwill Total fair value consideration Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Business Combinations Business Combination Disclosure [Text Block] Schedule of cash, cash equivalents and investments Cash, Cash Equivalents and Investments [Table Text Block] Summary of available-for-sale securities' adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Statement of Financial Position [Abstract] Accounts receivable, allowance Allowance for Doubtful Accounts Receivable Redeemable convertible preferred stock, shares issued (in shares) Temporary Equity, Shares Issued Redeemable convertible preferred stock, shares outstanding (in shares) Temporary Equity, Shares Outstanding Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Dispositions Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Fair Value Fair Value Disclosures [Text Block] Series A redeemable convertible preferred stock Temporary Equity, Stock Issued During Period, Value, New Issues Issuance costs Accretion of issuance costs Accretion Expense Stock dividend payable to preferred stockholders Dividends Payable Redeemable convertible preferred stock Temporary Equity, Carrying Amount, Attributable to Parent Purchase price Business Combination, Consideration Transferred Payments related to acquisition, net of cash acquired Payments to Acquire Businesses, Gross Stock issued for acquisition Stock Issued During Period, Shares, Acquisitions Contingent consideration related to acquisition Business Combination, Contingent Consideration, Liability Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Adjusted Cost Available-for-sale Securities, Amortized Cost Basis Unrealized Losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Fair Value Available-for-sale Securities Statement of Comprehensive Income [Abstract] Net loss Change in foreign currency translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent Change in net unrealized gain (loss) on marketable securities Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Other comprehensive (loss) income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Total comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of interest rates and amortization discount Schedule Of Interest Rates And Amortization Discount [Table Text Block] Schedule Of Interest Rates And Amortization Discount [Table Text Block] Numerator Net Income (Loss) Attributable to Parent [Abstract] Less: Stock dividend payable and transaction costs Redeemable Preferred Stock Dividends Net loss available to common stockholders Denominator Weighted Average Number of Shares Outstanding, Diluted [Abstract] Net loss per common share, basic and diluted (in dollars per share) Effective interest rate Debt Instrument, Interest Rate, Effective Percentage Contractually stated interest expense Interest Expense, Debt, Excluding Amortization Amortization of discount Amortization of Debt Discount (Premium) Schedule of long-term debt Schedule of Long-term Debt Instruments [Table Text Block] Summary of the effective interest rate, contractually stated interest expense and costs related to amortization of discount for the Notes Convertible Debt [Table Text Block] Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Patents Patents [Member] Developed technology Developed Technology Rights [Member] Customer relationships Customer Relationships, Users [Member] Customer Relationships, Users [Member] Trade names Trade Names [Member] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Finite-lived intangible assets Finite-Lived Intangible Assets, Net [Abstract] Gross Carrying Amount Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Content acquisition costs Payments for Royalties Total future minimum guarantee payments Royalty Guarantees, Commitments, Amount Future minimum guarantee commitments to be paid this year Royalty Guarantees, Commitments, Future Minimum Payments Due, Remainder of Fiscal Year Royalty Guarantees, Commitments, Future Minimum Payments Due, Remainder of Fiscal Year Schedule of fair value of financial assets and liabilities inputs Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Statement of Cash Flows [Abstract] Operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Adjustments to reconcile net loss to net cash used in operating activities Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Loss on dispositions Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal Loss on extinguishment of convertible debt Depreciation and amortization Depreciation, Depletion and Amortization Stock-based compensation Share-based Compensation Amortization of premium on investments, net Amortization Of Premium On Investments, Net Amortization Of Premium On Investments, Net Accretion of discount on convertible promissory note receivable Accretion Of Discount On Convertible Promissory Note Receivable Accretion Of Discount On Convertible Promissory Note Receivable Other operating activities Other Operating Activities, Cash Flow Statement Amortization of debt discount Amortization of Debt Issuance Costs and Discounts Interest income Interest Income, Operating Provision for bad debt Provision for Doubtful Accounts Changes in operating assets and liabilities Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Prepaid content acquisition costs Increase (Decrease) in Prepaid Royalties Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable, accrued and other current liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Accrued content acquisition costs Increase (Decrease) in Royalties Payable Accrued compensation Increase (Decrease) in Employee Related Liabilities Other long-term liabilities Increase (Decrease) in Other Noncurrent Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Reimbursement of cost of leasehold improvements Payments for (Proceeds from) Tenant Allowance Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations 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 Internal-use software costs Payments to Develop Software Payments related to acquisition, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Payments related to acquisition, net of cash acquired Payments to Acquire Investments Proceeds from maturities of investments Proceeds from Sale, Maturity and Collection of Investments Proceeds from cancellation of convertible promissory note receivable Proceeds from Collection of Notes Receivable Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations Financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Proceeds from issuance of redeemable convertible preferred stock Proceeds from Issuance of Redeemable Convertible Preferred Stock Payments of issuance costs Payments of Debt Issuance Costs Proceeds from employee stock purchase plan Proceeds from Stock Plans Proceeds from exercise of stock options Proceeds from Issuance of Common Stock Tax withholdings related to net share settlements of restricted stock units Payments Related to Tax Withholding for Share-based Compensation Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations Effect of exchange rate changes on cash, cash equivalents and restricted cash Effect of Exchange Rate on Cash and Cash Equivalents Net increase (decrease) 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 at beginning of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Less: Cash held for sale Cash Held-for-sale, Reconciliation to Cash Flow, Deductions from Held-for-sale Cash Held-for-sale, Reconciliation to Cash Flow, Deductions from Held-for-sale Cash, cash equivalents and restricted cash at end of period Supplemental disclosures of cash flow information Supplemental Cash Flow Information [Abstract] Purchases of property and equipment recorded in accounts payable and accrued liabilities Capital Expenditures Incurred but Not yet Paid Cash paid during the period for interest Interest Paid Accretion of preferred stock issuance costs Stock dividend payable to preferred stockholders Dividends, Preferred Stock Fair value of shares issued related to acquisition Business Acquisition, Equity Interest Issued or Issuable, Value Assigned Stock dividend payable to preferred stockholders Noncash Equity Stock Purchase Plan Purchases Increase (Decrease) in Noncash Equity Liability Reconciliation of cash, cash equivalents and restricted cash as shown in the statements of cash flows Restricted Cash and Cash Equivalents [Abstract] Cash and cash equivalents Restricted cash included in other long-term assets line item of Condensed Consolidated Balance Sheets Restricted Cash Equivalents, Noncurrent Total cash, cash equivalents and restricted cash RSUs Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Assets Assets [Abstract] Current assets Assets, Current [Abstract] Short-term investments Accounts receivable, net of allowance of $5,352 at December 31, 2017 and $5,935 at June 30, 2018 Receivables, Net, Current Prepaid content acquisition costs Prepaid Royalties Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Property and equipment, net Property, Plant and Equipment, Net Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Other long-term assets Other Assets, Noncurrent Total assets Assets Liabilities, redeemable convertible preferred stock and stockholders’ equity Liabilities and Equity [Abstract] Current liabilities Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued liabilities Accrued Liabilities, Current Accrued content acquisition costs Accrued Royalties, Current Accrued compensation Employee-related Liabilities, Current Deferred revenue Deferred Revenue, Current Total current liabilities Liabilities, Current Other long-term liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Redeemable convertible preferred stock: 480,000 shares issued and outstanding at December 31, 2017 and 480,000 at June 30, 2018 Temporary Equity, Carrying Amount, Including Portion Attributable to Noncontrolling Interests Stockholders’ equity Stockholders' Equity Attributable to Parent [Abstract] Common stock: 250,867,462 shares issued and outstanding at December 31, 2017 and 266,317,032 at June 30, 2018 Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Accumulated deficit Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities, redeemable convertible preferred stock and stockholders’ equity Liabilities and Equity Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Redeemable Convertible Preferred Stock Stockholders' Equity Note Disclosure [Text Block]