Equity [Abstract] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Unrealized Gain (Loss) on Investments, net of tax Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Foreign Currency Translation Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Beginning Balance Stockholders' Equity Attributable to Parent Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Ending Balance Earnings Per Share [Abstract] Basic EPS: Earnings Per Share, Basic [Abstract] Net income (loss) Net Income (Loss) Attributable to Parent Weighted-average common shares outstanding Weighted Average Number of Shares Issued, Basic Weighted-average unvested restricted shares Weighted Average Number of Shares, Restricted Stock Weighted-average escrow shares Weighted Average Number of Shares, Contingently Issuable Weighted-average common shares outstanding used to compute net income (loss) per share Weighted Average Number of Shares Outstanding, Basic Basic net income (loss) per share (usd per share) Earnings Per Share, Basic Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Stock Option Employee Stock Option [Member] Unvested restricted stock awards Restricted Stock [Member] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] ESPP Employee Stock [Member] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Diluted EPS: Earnings Per Share, Diluted [Abstract] Net income (loss) Weighted-average common shares used in basic EPS Dilutive effect of weighted-average share-based compensation (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Dilutive effect of weighted-average escrow shares (in shares) Incremental Common Shares Attributable To Dilutive Effect Of Escrow Shares Incremental Common Shares Attributable To Dilutive Effect Of Escrow Shares Dilutive effect of weighted-average contingent shares (in shares) Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares Weighted-average shares used to compute diluted net income (loss) per share attributable to common stockholders (in shares) Weighted Average Number of Shares Outstanding, Diluted Diluted net income (loss) per share attributable to common stockholders (usd per share) Earnings Per Share, Diluted Commitments and Contingencies Disclosure [Abstract] Operating lease obligations Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 2018 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2019 Operating Leases, Future Minimum Payments, Due in Two Years 2020 Operating Leases, Future Minimum Payments, Due in Three Years 2021 Operating Leases, Future Minimum Payments, Due in Four Years 2022 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total Operating Leases, Future Minimum Payments Due Operating sublease income Operating Leases, Rent Expense, Net [Abstract] 2018 Operating Leases Rent Expense Sublease Rentals Due Next Twelve Months Operating Leases Rent Expense Sublease Rentals Due Next Twelve Months 2019 Operating Leases Rent Expense Sublease Rentals Due in Two Years Operating Leases Rent Expense Sublease Rentals Due in Two Years 2020 Operating Leases Rent Expense Sublease Rentals Due in Three Years Operating Leases Rent Expense Sublease Rentals Due in Three Years 2021 Operating Leases Rent Expense Sublease Rentals Due in Four Years Operating Leases Rent Expense Sublease Rentals Due in Four Years 2022 Operating Leases Rent Expense Sublease Rentals Due in Five Years Operating Leases Rent Expense Sublease Rentals Due in Five Years Thereafter Operating Leases Rent Expense Sublease Rentals Due Thereafter Operating Leases Rent Expense Sublease Rentals Due Thereafter Total Operating Leases, Rent Expense, Sublease Rentals Due Operating Leases, Rent Expense, Sublease Rentals Due Total lease obligations and sublease income Operating Leases, Future Minimum Payments Due, Rolling Maturity [Abstract] 2018 Operating Leases Rent Expense Net, Next Twelve Months Operating Leases Rent Expense Net, Next Twelve Months 2019 Operating Leases Rent Expense Net, in Two Years Operating Leases Rent Expense Net, in Two Years 2020 Operating Leases Rent Expense Net, in Three Years Operating Leases Rent Expense Net, in Three Years 2021 Operating Leases Rent Expense Net, in Four Years Operating Leases Rent Expense Net, in Four Years 2022 Operating Leases Rent Expense Net, in Five Years Operating Leases Rent Expense Net, in Five Years Thereafter Operating Leases Rent Expense Net, Thereafter Operating Leases Rent Expense Net, Thereafter Total Operating Leases, Rent Expense, Net Due Operating Leases, Rent Expense, Net Due Other Commitments [Table] Other Commitments [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] Office Lease Office Lease [Member] Office Lease [Member] 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] Other Commitments [Line Items] Other Commitments [Line Items] Rental expense Operating Leases, Rent Expense Rent expense for sublease rentals Operating Leases, Rent Expense, Sublease Rentals New letters of credit entered into during period Letters Of Credit, Additional During Period Letters Of Credit, Additional During Period Letters of credit outstanding, amount Letters of Credit Outstanding, Amount Income Tax Disclosure [Abstract] 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 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 Compensation Cost, Percent Meals and entertainment Effective Income Tax Rate Reconciliation, Nondeductible Expense, Meals and Entertainment, Percent Acquisition and related items Effective Income Tax Rate Reconciliation, Acquisition, Percent Effective Income Tax Rate Reconciliation, Acquisition, Percent Goodwill impairment Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent Non-deductible gifts Effective Income Tax Rate Reconciliation, Nondeductible Expense, Gifts, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Gifts, Percent Research and development tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent Tax effect of intercompany financing Effective Income Tax Rate Reconciliation, Intercompany Financing Charges Effective Income Tax Rate Reconciliation, Intercompany Financing Charges Worthless stock Effective Income Tax Rate Reconciliation, Stock With No Value Effective Income Tax Rate Reconciliation, Stock With No Value Other permanent items Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent Provision (benefit) to return adjustments Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Percent Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Tax rate change; U.S. tax reform Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Effective income tax rate Effective Income Tax Rate Reconciliation, Percent 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 Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Data (Unaudited) Quarterly Financial Information [Text Block] Benefit for income taxes Income Tax Expense (Benefit) Tax benefit related to worthless stock deduction Income Tax Expense (Benefit) Related To Worthless Stock Income Tax Expense (Benefit) Related To Worthless Stock Income tax benefit, net of valuation allowance related to worthless stock deduction Income Tax Expense (Benefit) Related To Worthless Stock, Net Of Valuation Allowance Income Tax Expense (Benefit) Related To Worthless Stock, Net Of Valuation Allowance Provisional Transition Tax which reduced U.S. net deferred tax assets Tax Cuts And Jobs Act Of 2017 Incomplete Accounting Provisional Income Tax Expense Benefit Amount of reasonable estimate for income tax expense (benefit) from effect of Tax Cuts and Jobs Act for which accounting for tax effect is incomplete. Decrease to U.S. net deferred tax assets Tax Cuts And Jobs Act Of 2017 Incomplete Accounting Change In Tax Rate Deferred Tax Asset Provisional Income Tax Expense Amount of reasonable estimate for income tax expense for remeasurement of deferred tax asset from change in tax rate pursuant to Tax Cuts and Jobs Act for which accounting for tax effect is incomplete. Write-off recorded due to new Tax Act Tax Cuts and Jobs Act, Change in Tax Rate, Write-Off Tax Cuts and Jobs Act, Change in Tax Rate, Write-Off Tax Credit Carryforward [Table] Tax Credit Carryforward [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] Foreign Tax Authority Foreign Tax Authority [Member] Domestic Tax Authority Domestic Tax Authority [Member] State and Local Jurisdiction State and Local Jurisdiction [Member] Tax Credit Carryforward [Line Items] Tax Credit Carryforward [Line Items] Tax credit carryforwards Tax Credit Carryforward, Amount Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Net deferred tax assets related to net operating losses for income tax benefits Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount Operating loss carryforwards Operating Loss Carryforwards Change in valuation allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Unremitted earnings of the subsidiaries outside of the United States Undistributed Earnings of Foreign Subsidiaries Provisional transition tax related to unremitted earnings of subsidiaries outside United States Tax Cuts And Jobs Act Of 2017 Incomplete Accounting Transition Tax For Accumulated Foreign Earnings Provisional Income Tax Expense Amount of reasonable estimate for income tax expense from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act for which accounting for tax effect is incomplete. Business Combinations [Abstract] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] nToggle nToggle [Member] nToggle [Member] 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] 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] Acquired intangible assets Finite-lived Intangible Assets Acquired Estimated useful lives of acquired intangible assets Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Disclosure of Compensation Related Costs, Share-based Payments [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] Employee Stock 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 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] Unvested restricted stock units Shares held in escrow Shares Held in Escrow [Member] Shares Held in Escrow [Member] Employee Stock Purchase Plan Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Contingent Shares Contingent Shares [Member] Contingent Shares [Member] Chango Chango Inc [Member] Chango Inc [Member] iSocket iSocket, Inc [Member] iSocket, Inc [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 Contingent consideration, shares issued Business Combination, Contingent Consideration, Shares Issued Business Combination, Contingent Consideration, Shares Issued Contingent consideration, shares released from escrow Business Combination, Contingent Consideration, Shares Released From Escrow Business Combination, Contingent Consideration, Shares Released From Escrow Investments, Debt and Equity Securities [Abstract] Due in less than 1 year, Amortized Cost Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis Due within 1-2 years, Amortized Cost Available-for-sale Securities, Debt Maturities, Year One Through Two, Amortized Cost Basis Available-for-sale Securities, Debt Maturities, Year One Through Two, Amortized Cost Basis Total, Amortized Cost Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis Due in less than 1 year, Fair Value Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value Due within 1-2 years, Fair Value Available-for-sale Securities, Debt Maturities, Year One Through Two, Fair Value Available-for-sale Securities, Debt Maturities, Year One Through Two, Fair Value Total, Fair Value Available-for-sale Securities, Debt Maturities, Single Maturity Date Schedule of Share-based Compensation, Stock Options, Activity Share-based Compensation, Stock Options, 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 Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] Accounting Policies [Abstract] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Developed technology Customer relationships Customer Relationships [Member] Other intangible assets Other Intangible Assets [Member] Software development Software Development [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Useful lives Finite-Lived Intangible Asset, Useful Life Restructuring and Related Activities [Abstract] Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Accrued restructuring and other exit costs at December 31, 2016 Restructuring Reserve Restructuring and other exit costs Restructuring Charges Cash paid for restructuring and other exit costs Payments for Restructuring Non-cash stock-based compensation for restructuring and other exit costs Restructuring Reserve, Settled without Cash Accrued restructuring and other exit costs at December 31, 2017 Restructuring and other exit costs Restructuring Charges [Abstract] Employee termination costs Severance Costs Facility closing costs Business Exit Costs Total restructuring and other exit costs Fair Value Disclosures [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Valuation Technique [Axis] Valuation Technique [Axis] Valuation Technique [Domain] Valuation Technique [Domain] Income Approach Valuation Technique [Member] Income Approach Valuation Technique [Member] Market Approach Valuation Technique [Member] Market Approach Valuation Technique [Member] Common Stock Common Stock [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [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] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Recurring Fair Value, Measurements, Recurring [Member] Nonrecurring Fair Value, Measurements, Nonrecurring [Member] Asset Class [Axis] Asset Class [Axis] Asset Class [Domain] Asset Class [Domain] Finite-Lived Intangible Assets Finite-Lived Intangible Assets [Member] Class of Stock [Line Items] Class of Stock [Line Items] Change in fair value of contingent consideration Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Fair Value Inputs, Discount Rate Fair Value Inputs, Discount Rate Fair Value Inputs, Control Premium Fair Value Inputs, Control Premium EBITDA multiple used for fair value Fair Value Inputs, Earnings before Interest, Taxes, Depreciation, and Amortization Multiple Impairment of goodwill Goodwill, Impairment Loss Goodwill Goodwill Asset impairment charges Asset Impairment Charges Intangible Assets, Net (Including Goodwill) Intangible Assets, Net (Including Goodwill) Quarterly Financial Data (Unaudited) Quarterly Financial Information [Table Text Block] Goodwill and Intangible Assets Disclosure [Abstract] 2018 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 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 Total Finite-Lived Intangible Assets, Net Property, Plant and Equipment [Abstract] Property and Equipment Property, Plant and Equipment Disclosure [Text Block] 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 Statement of Financial Position [Abstract] 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, Net, Current 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 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. Other assets, non-current Other Assets, Noncurrent Intangible assets, net Intangible Assets, Net (Excluding Goodwill) TOTAL ASSETS Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] LIABILITIES Liabilities [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable and accrued expenses Accounts Payable and Accrued Liabilities, Current Other current liabilities Other Liabilities, Current TOTAL CURRENT LIABILITIES Liabilities, Current Deferred tax liability, net Other Liabilities, Noncurrent Deferred tax liability, net Deferred Tax Liabilities, Net, Noncurrent TOTAL LIABILITIES Liabilities Commitments and contingencies (Note 17) Commitments and Contingencies STOCKHOLDERS' EQUITY Stockholders' Equity Attributable to Parent [Abstract] Common stock, $0.00001 par value; 500,000 shares authorized at December 31, 2017 and 2016; 50,239 and 49,378 shares issued and outstanding at December 31, 2017 and 2016, 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 Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Line Items] Business Acquisition [Line Items] Shares of the Company's common stock Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Estimated fair value of contingent consideration Business Combination, Contingent Consideration, Liability Fair value of stock-based awards exchanged Business Combination, Consideration Transferred, Stock Options Exchanged Business Combination, Consideration Transferred, Stock Options Exchanged Cash paid Business Combination, Outstanding Debt and Transaction expenses, Cash Paid Business Combination, Outstanding Debt and Transaction expenses, Cash Paid Working capital adjustment Business Combination, Consideration Transfered, Working Capital Adjustment Business Combination, Consideration Transfered, Working Capital Adjustment Total purchase consideration Business Combination, Consideration Transferred and Contingent Consideration Business Combination, Consideration Transferred and Contingent Consideration Cash acquired 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 Fixed assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Other non-current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent 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, Accounts Payable Deferred revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Liabilities Deferred tax liability, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent Total liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Net assets acquired Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Number of operating segments Number of Operating Segments Stock-based compensation award requisite service period Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period Tax benefit from compensation expense Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Dividend yield Fair Value Assumptions, Expected Dividend Rate Restricted cash included in prepaid expenses and other current assets Restricted Cash and Cash Equivalents, Current Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable Allowance for doubtful accounts, write-offs Allowance for Doubtful Accounts Receivable, Write-offs Impairment of goodwill Concentration Risk [Table] Concentration Risk [Table] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Credit Concentration Risk Credit Concentration Risk [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Accounts Receivable Accounts Receivable [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Customer 1 Customer One [Member] Customer One [Member] Customer 2 Customer Two [Member] Customer Two [Member] Concentration Risk [Line Items] Concentration Risk [Line Items] Concentration risk, percentage Concentration Risk, Percentage Common stock, shares authorized Common Stock, Shares Authorized Preferred stock, shares authorized Preferred Stock, Shares Authorized Number of shares reserved Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Investment Type [Axis] Investment Type [Axis] Investments [Domain] Investments [Domain] Money Market Funds [Member] Money Market Funds [Member] Corporate debt securities Corporate Debt Securities [Member] U.S. Treasury, government and agency debt securities US Treasury and Government [Member] Short-term investments Short-term Investments [Member] Fair Value, Measurements, Recurring 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] Available-for-sale Securities Available-for-sale Securities Research and Development [Abstract] Internal Use Software Development Costs Research, Development, and Computer Software Disclosure [Text Block] 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, 2018 Capitalized Computer Software, Amortization Expense, Next Twelve Months Capitalized Computer Software, Amortization Expense, Next Twelve Months Estimated amortization expense, 2019 Capitalized Computer Software, Amortization Expense, Year Two Capitalized Computer Software, Amortization Expense, Year Two Estimated amortization expense, 2020 Capitalized Computer Software, Amortization Expense, Year Three Capitalized Computer Software, Amortization Expense, Year Three 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] Business Acquisition, Pro Forma Information Business Acquisition, Pro Forma Information [Table Text Block] Income Statement [Abstract] Revenue Revenues Expenses: Costs and Expenses [Abstract] 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 Impairment of intangible assets and internal use software Total expenses Costs and Expenses Loss from operations Operating Income (Loss) 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, net Nonoperating Income (Expense) Loss before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Net income (loss) Net income (loss) per share: Basic (usd per share) Diluted (usd per share) Weighted-average shares used to compute net income (loss) per share: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Diluted (in shares) Statement of Comprehensive Income [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Unrealized gain (loss) on investments Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of 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) Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Document and Entity Information [Abstract] Document and Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Public Float Entity Public Float Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Pro forma revenues Business Acquisition, Pro Forma Revenue Pro forma net income (loss) Business Acquisition, Pro Forma Net Income (Loss) Pro forma net income (loss) per share, basic (usd per share) Business Acquisition, Pro Forma Earnings Per Share, Basic Pro forma net income(loss) per share, diluted (usd per share) Business Acquisition, Pro Forma Earnings Per Share, Diluted Stock-Based Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Business Combinations Business Combination Disclosure [Text Block] Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Forecast Scenario, Forecast [Member] Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Axis] Effects on Future Earnings and Cash Flows Resulting from Exit Plan [Axis] Effects on Future Earnings and Cash Flows, by Type of Effect [Domain] Effects on Future Earnings and Cash Flows, by Type of Effect [Domain] Reduced Employee Expenses Reduced Employee Expenses [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Number of employees in headcount reduction (approximately) Restructuring and Related Cost, Number of Positions Eliminated Number of employees in headcount reduction, percentage Restructuring and Related Cost, Number of Positions Eliminated, Period Percent Headcount, number of employees Entity Number of Employees Severance costs Net offset to operating expenses Effect on Future Earnings, Offset, Net Of Severance Costs Effect on Future Earnings, Offset, Net Of Severance Costs Expected offset to future cash expenses annually Effect on Future Cash Flows, Amount Risk-free interest rate (in percentage) Expected volatility (in percentage) Dividend yield (in percentage) Weighted remaining contractual maturity Available-for-sale Securities, Weighted-average Remaining Contractual Maturity Available-for-sale Securities, Weighted-average Remaining Contractual Maturity Realized gains (losses) Realized Investment Gains (Losses) Trading Securities, Unrealized Holding Gain Trading Securities, Unrealized Holding Gain Segment Reporting [Abstract] Geographic Information Segment Reporting Disclosure [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] Vesting Period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Additional Paid-In Capital Additional Paid-in Capital [Member] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2016-09 [Member] Accounting Standards Update 2016-09 [Member] New Accounting Pronouncement, Early Adoption [Axis] New Accounting Pronouncement, Early Adoption [Axis] New Accounting Principles, Early Adoption [Domain] New Accounting Principles, Early Adoption [Domain] New Accounting Pronouncement, Early Adoption, Effect [Member] New Accounting Pronouncement, Early Adoption, Effect [Member] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2014 Equity Incentive Plan 2014 Equity Incentive Plan [Member] 2014 Equity Incentive Plan [Member] Award Vesting Rights, Percentage Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Evergreen provision, automatic annual increase in share reserve (as a percent) Evergreen Annual % Increase Evergreen Annual % Increase Cumulative-effect adjustment Cumulative Effect of New Accounting Principle in Period of Adoption Number of Shares Available for Grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Payables and Accruals [Abstract] 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 Accounts payable and accrued expenses Subsequent Events Subsequent Events [Text Block] Other (income) expense, net Provision (benefit) for income taxes Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Weighted Average Grant Date Value Per Share Share-based Compensation Award, Tranche Three [Member] Unrecognized employee stock-based compensation Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options Unrecognized employee stock-based compensation, period for recognition Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Fair value of awards Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Intrinsic value of nonvested unit Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Beginning Balance Unrecognized Tax Benefits Increases related to current year tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions 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 Ending Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Unrecognized employee stock-based compensation Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options Weighted average grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Options outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Stock-based compensation expense Allocated Share-based Compensation Expense Depreciation expense on property and equipment Depreciation Impairment of long-lived assets Impairment of Long-Lived Assets Held-for-use Property and equipment under capital leases Capital Leased Assets, Gross Trademarks [Member] Trademarks [Member] Amortizable intangible assets, gross Finite-Lived Intangible Assets, Gross Total accumulated amortization—intangible assets Finite-Lived Intangible Assets, Accumulated Amortization Basis of Consolidation Consolidation, Policy [Policy Text Block] Segments Segment Reporting, Policy [Policy Text Block] Reclassifications Reclassification, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Cost of Revenue Cost of Sales, Policy [Policy Text Block] Sales and Marketing Advertising Costs, Policy [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] Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block] Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block] Stock-Based Compensation Share-based Compensation, Option and Incentive Plans Policy [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 Marketable Securities Cash and Cash Equivalents and Marketable Securities, Policy [Policy Text Block] Cash and Cash Equivalents and Marketable Securities, Policy [Policy Text Block] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, 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 Capital 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 Translations Foreign Currency Transactions and Translations Policy [Policy Text Block] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Debt Disclosure [Abstract] Debt Debt and Capital Leases Disclosures [Text Block] 2014 Employee Stock Purchase Plan 2014 Employee Stock Purchase Plan [Member] 2014 Employee Stock Purchase Plan [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 Increase in shares authorized, percent of outstanding stock Share-based Compensation Arrangement by Share-based Payment Award, Increase in Shares Authorized, Percent of Outstanding Stock Share-based Compensation Arrangement by Share-based Payment Award, Increase in Shares Authorized, Percent of Outstanding Stock Issuance of common stock related to employee stock purchase plan (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Restructuring and Other Exit Costs Restructuring and Related Activities Disclosure [Text Block] Beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Canceled Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Ending balance 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) 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) Related Party Transactions [Abstract] Revenue from related parties Revenue from Related Parties Schedule of Restructuring and Other Exit Costs Restructuring and Related Costs [Table Text Block] Net Income (Loss) Per Share Earnings Per Share [Text Block] 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 Investments in Marketable Securities Marketable Securities [Table Text Block] Amortized Cost and Fair Value of the Company's Marketable Securities Investments Classified by Contractual Maturity Date [Table Text Block] Vesting, Requisite Service Conditions Vesting, Requisite Service Conditions [Member] Vesting, Requisite Service Conditions [Member] Vesting, Market Conditions Vesting, Marketing Conditions [Member] Vesting, Marketing Conditions [Member] Vesting, Stock Price Performance Vesting, Stock Price Performance [Member] Vesting, Stock Price Performance [Member] Weighted average period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms 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] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Estimated useful life Property, Plant and Equipment, Useful Life Schedule of Future Minimum Rental Payments for Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Statement of Cash Flows [Abstract] OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income (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 Depreciation, Depletion and Amortization Stock-based compensation Share-based Compensation Loss on disposal of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Provision for doubtful accounts Provision for Doubtful Accounts Accretion of available for sale securities Accretion Of Available-For-Sale Securities Accretion Of Available-For-Sale Securities Unrealized foreign currency gains, net Foreign Currency Transaction Gain (Loss), Unrealized Impairment of intangible assets and internal use software Impairment of Intangible Assets, Finite-lived Deferred income taxes Deferred Income Taxes and Tax Credits 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 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 Payments to Acquire Businesses, Net of Cash Acquired Investments in available-for-sale securities Payments to Acquire Available-for-sale Securities Maturities of available-for-sale securities Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Net cash 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 From Issuances of Common Stock Under ESPP Proceeds From Issuances of Common Stock Under ESPP - represents cash inflow related to common stock issuances related to Employee Stock Purchase Plan Taxes paid related to net share settlement Payments Related to Tax Withholding for Share-based Compensation Repayment of debt and capital lease obligations Repayments of Debt and Capital Lease Obligations Net cash provided by (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 and Cash Equivalents CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH Cash and Cash Equivalents, Period Increase (Decrease) 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 Capitalized assets financed by accounts payable and accrued expenses Capital Expenditures Incurred but Not yet Paid Capitalized stock-based compensation Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount Common stock and options issued for business acquisitions Stock Issued Conversion of contingent consideration to common stock Business Acquisition, Conversion Of Contingent Consideration To Equity Instruments Issued, Value Assigned Business Acquisition, Conversion Of Contingent Consideration To Equity Instruments Issued, Value Assigned Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Purchased software Computer Software, Intangible Asset [Member] Computer equipment and network hardware Furniture, fixtures and office equipment Leasehold improvements Leasehold Improvements [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 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] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Organization and Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES United Kingdom UNITED KINGDOM Other international Other International [Member] Other International [Member] Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Technology-based intangible asset and customer relationships Technology-Based Intangible Asset and Customer Relationships [Member] Technology-Based Intangible Asset and Customer Relationships [Member] Goodwill [Line Items] Goodwill [Line Items] Nets assets carrying value prior to impairment Net Asset Carrying Value Prior to Impairment Net Asset Carrying Value Prior to Impairment Amortization expense of intangible assets Amortization of Intangible Assets Increase in amortization expense Change In Estimated Useful Lives, Effect Of Change On Amortization Expense Change In Estimated Useful Lives, Effect Of Change On Amortization Expense Decrease in basic earnings per share due to increase in amortization expense (usd per share) Change In Estimated Useful Lives, Effect Of Change On Basic Earnings Per Share Change In Estimated Useful Lives, Effect Of Change On Basic Earnings Per Share Decrease in diluted earnings per share due to increase in amortization expense (usd per share) Change In Estimated Useful Lives, Effect Of Change On Diluted Earnings Per Share Change In Estimated Useful Lives, Effect Of Change On Diluted Earnings Per Share Goodwill [Roll Forward] Goodwill [Roll Forward] Beginning balance Additions from the acquisition of nToggle (See Note 7) Goodwill, Acquired During Period Impairment of goodwill Ending balance Common stock, par or stated value per share Common Stock, Par or Stated Value Per Share Common stock, shares, issued Common Stock, Shares, Issued Common stock, shares, outstanding Common Stock, Shares, Outstanding Restricted Stock Awards Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] General and Administrative Expense General and Administrative Expense [Member] Payments to Acquire Businesses, Net of Cash Acquired Business Combination, Consideration Transferred Business Combination, Consideration Transferred Cash Acquired from Acquisition Cash Acquired from Acquisition Business Combination, In-The-Money Options Assumed Business Combination, In-The-Money Options Assumed Business Combination, In-The-Money Options Assumed Business Combination, Restricted Stock Assumed Business Combination, Restricted Stock Assumed Business Combination, Restricted Stock Assumed Equity interest issued, number of shares Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Acquisition related costs Business Combination, Acquisition Related Costs Net operating loss acquired Business Combination, Net Operating Loss Acquired Business Combination, Net Operating Loss Acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Fair value of common stock Indemnification assets, shares held in escrow Business Combination, Indemnification Assets, Shares Held in Escrow Business Combination, Indemnification Assets, Shares Held in Escrow Business Combination, Future Service, Shares Held in Escrow Business Combination, Future Service, Shares Held in Escrow Business Combination, Future Service, Shares Held in Escrow Cash paid for outstanding debt and transaction expenses Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High Business Combination, Contingent Consideration, Shares Held in Escrow Business Combination, Contingent Consideration, Shares Held in Escrow Business Combination, Contingent Consideration, Shares Held in Escrow Business Combination, Contingent Consideration, Stock Price Trigger Business Combination, Contingent Consideration, Stock Price Trigger Business Combination, Contingent Consideration, Stock Price Trigger Fair value of contingent consideration Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Options Issued Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Options Issued Fair value attributed to pre-acquisition stock options exchanged Goodwill, Other Changes Goodwill, Other Increase (Decrease) Intangible liabilities Deferred Tax Liabilities, Intangible Assets Total deferred tax assets Deferred Tax Assets, Gross Deferred Taxes, Business Combination, Valuation Allowance, Available to Reduce Income Tax Expense Deferred Taxes, Business Combination, Valuation Allowance, Available to Reduce Income Tax Expense Investments Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Schedule Of Internal Use Software Costs Schedule Of Internal Use Software Costs [Table Text Block] Schedule of Internal Use Software Costs [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 Research tax credit carryovers Deferred Tax Assets, Tax Credit Carryforwards, Research Other Deferred Tax Assets, Other Total deferred tax assets 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 Other Deferred Tax Liabilities, Other Total deferred tax liabilities Deferred Tax Liabilities, Gross Net deferred tax assets (liability) Deferred Tax Assets, Net Income Taxes Income Tax Disclosure [Text Block] Revenue from External Customers by Geographic Areas [Table Text Block] Revenue from External Customers by Geographic Areas [Table Text Block] Long-lived Assets by Geographic Areas Long-lived Assets by Geographic Areas [Table Text Block] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Accumulated Other Comprehensive Income (Loss) 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) 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 Shares withheld related to net share settlement (in shares) Shares Paid for Tax Withholding for Share Based Compensation Shares withheld related to net share settlement Adjustments Related to Tax Withholding for Share-based Compensation Issuance of common stock related to RSU vesting (in shares) Stock Issued During Period, Shares, Share-based Compensation, Gross Issuance of common stock related to RSU vesting Stock Issued During Period, Value, Employee Stock Purchase Plan Issuance of common stock related to acquisition (in shares) Stock Issued During Period, Shares, Acquisitions Issuance of common stock related to acquisition Stock Issued During Period, Value, Acquisitions Issuance of common stock for contingent consideration associated with acquisitions (in shares) Stock Issued During Period, Shares, Acquisitions, Contingent Consideration Stock Issued During Period, Shares, Acquisitions, Contingent Consideration Issuance of common stock for contingent consideration associated with acquisitions Stock Issued During Period, Value, Acquisitions, Contingent Consideration Stock Issued During Period, Value, Acquisitions, Contingent Consideration Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Other comprehensive loss Other Comprehensive Income (Loss), Foreign Currency Translation Gain (Loss) Arising During Period, Tax Ending Balance (in shares) 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) 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] Granted (in dollars per share) Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Expired (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Forfeited (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Ending balance (in dollars per share) 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 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] Exercisable (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Exercisable (in dollars 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 Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Fair Value, Assets Measured on Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Long-term investments Other Long-term Investments [Member] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] U.S. Treasury, government and agency debt securities Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Amortized Cost Available-for-sale Debt Securities, Amortized Cost Basis Gross Unrealized Gains Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax Fair Value Available-for-sale Securities, Debt Securities 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] 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 Restructuring and other exit costs Restructuring Charges [Member] Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] Schedule of Accounts Payable and Accrued Liabilities Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Schedule of Finite-Lived Intangible Assets 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] Organization, Consolidation and Presentation of Financial Statements [Abstract] Nature of Operations Nature of Operations [Text Block] Related Party Transactions Related Party Transactions Disclosure [Text Block] Line of Credit Facility [Table] Line of Credit Facility [Table] Lender Name [Axis] Lender Name [Axis] Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Silicon Valley Bank Silicon Valley Bank [Member] Silicon Valley Bank [Member] 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] 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] Prime Rate Prime Rate [Member] London Interbank Offered Rate (LIBOR) London Interbank Offered Rate (LIBOR) [Member] Net Cash Balance Exceeding One Dollar, Maintained Net Cash Balance Exceeding One Dollar, Maintained [Member] Net Cash Balance Exceeding One Dollar, Maintained [Member] Net Cash Balance Exceeding One Dollar, Not Maintained Net Cash Balance Exceeding One Dollar, Not Maintained [Member] Net Cash Balance Exceeding One Dollar, Not Maintained [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 Debt instrument, basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Debt instrument, minimum net cash balance before increase in variable rate Debt Instrument, Minimum Net Cash Balance Before Increase in Variable Rate Debt Instrument, Minimum Net Cash Balance Before Increase in Variable Rate Line of credit facility, unused capacity, commitment fee percentage Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Debt instrument, covenant, fixed charge coverage ratio, minimum allowed Debt Instrument, Covenant, Minimum Fixed Charge Coverage Ratio Debt Instrument, Covenant, Minimum Fixed Charge Coverage Ratio Debt instrument, covenant, fixed charge coverage ratio, calculation period Debt Instrument, Covenant, Fixed Charge Coverage Ratio, Calculation Period Debt Instrument, Covenant, Fixed Charge Coverage Ratio, Calculation Period Line of credit Long-term Line of Credit Debt instrument, covenant, minimum remaining borrowing capacity threshold, percent Debt Instrument, Covenant, Minimum Remaining Borrowing Capacity Threshold, Percent Debt Instrument, Covenant, Minimum Remaining Borrowing Capacity Threshold, Percent Debt Instrument, Maturity Date Debt Instrument, Maturity Date Fair Value Measurements Fair Value Disclosures [Text Block] Accounts Payable and Accrued Expense Accounts Payable and Accrued Liabilities Disclosure [Text Block]