Intangible Assets, Net (Including Goodwill) [Abstract] INTANGIBLE ASSETS AND GOODWILL Goodwill and Intangible Assets Disclosure [Text Block] Debt Disclosure [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Convertible Debt Convertible Debt [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Aggregate Notes Aggregate Notes [Member] Aggregate Notes [Member] Initial Notes Initial Notes [Member] [Member] Initial Notes [Member] Additional Notes Additional Notes [Member] Additional Notes [Member] Option Indexed to Issuer's Equity, Type [Axis] Option Indexed to Issuer's Equity, Type [Axis] Option Indexed to Issuer's Equity, Type [Domain] Option Indexed to Issuer's Equity, Type [Domain] Call Option Call Option [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Debt instrument, face value Debt Instrument, Face Amount Debt instrument, interest rate Debt Instrument, Interest Rate, Stated Percentage Proceeds from issuance of debt Proceeds from Debt, Net of Issuance Costs Debt instrument, convertible, conversion ratio Debt Instrument, Convertible, Conversion Ratio Common stock, par value per share (in dollars per share) Common Stock, Par or Stated Value Per Share Debt instrument, convertible, conversion price (in dollars per share) Debt Instrument, Convertible, Conversion Price Debt instrument, redemption price, percentage Debt Instrument, Redemption Price, Percentage Debt instrument, convertible, threshold percentage of stock price trigger Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger Debt instrument, convertible, threshold trading days Debt Instrument, Convertible, Threshold Trading Days Debt instrument, convertible, threshold consecutive trading days Debt Instrument, Convertible, Threshold Consecutive Trading Days Debt instrument, strike price per share (in dollars per share) Option Indexed to Issuer's Equity, Strike Price Debt instrument, initial cap price per share (in dollars per share) Option Indexed To Issuer's Equity, Cap Price Option Indexed To Issuer's Equity, Cap Price Option indexed to issuer's equity, indexed shares (in shares) Option Indexed to Issuer's Equity, Indexed Shares Payments for capped call transactions Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt, Subsequent Adjustments Remaining 2020 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2024 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Net Carrying Amount Finite-Lived Intangible Assets, Net Leases [Abstract] Weighted average remaining lease term Operating Lease, Weighted Average Remaining Lease Term Weighted average discount rate Operating Lease, Weighted Average Discount Rate, Percent Operating cash flow from operating leases Operating Lease, Payments Business Combinations [Abstract] 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] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Trade and domain names Trade Names [Member] Trade and domain names Technology-Based Intangible Assets [Member] Customer relationships Customer Relationships [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Wavecell Pte. Ltd. Wavecell Pte. Ltd. [Member] Wavecell Pte. Ltd. [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Total intangible assets Finite-lived Intangible Assets Acquired Useful life (in Years) Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Cover page. Document Type Document Type Document Quarterly Report Document Quarterly Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Central Index Key Entity Central Index Key Amendment Flag Amendment Flag Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Period Focus Document Fiscal Period Focus Document Fiscal Year Focus Document Fiscal Year Focus Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES International Non-US [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Total revenue Revenue from Contract with Customer, Excluding Assessed Tax Share-based Payment Arrangement [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2017 Repurchase Plan 2017 Repurchase Plan [Member] 2017 Repurchase Plan [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Authorized repurchase amount Stock Repurchase Program, Authorized Amount Remaining authorized repurchase amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Stock repurchased during period (in shares) Stock Repurchased During Period, Shares STOCK-BASED COMPENSATION Shareholders' Equity and Share-based Payments [Text Block] Revenue from Contract with Customer [Abstract] Contract assets Contract With Customer, Asset Contract With Customer, Asset Change in contract assets Increase (Decrease) in Contract with Customer, Asset Deferred revenue Contract with Customer, Liability Change in deferred revenue Increase (Decrease) in Contract with Customer, Liability Assets and Liabilities, Leases Assets and Liabilities, Lessee [Table Text Block] Assets and Liabilities, Lessee [Table Text Block] Lease, Cost Lease, Cost [Table Text Block] Lessee, Operating Leases, Liability, Maturity Lessee, Operating Lease, Liability, Maturity [Table Text Block] Statement of Comprehensive Income [Abstract] Net loss Net Income (Loss) Attributable to Parent Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent [Abstract] Unrealized gain (loss) on investments in securities Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, before Tax Foreign currency translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Carrying Value of 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] Schedule of Goodwill Schedule of Goodwill [Table Text Block] Accounting Policies [Abstract] SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Significant Accounting Policies [Text Block] Assets Operating Lease, Right-Of-Use Asset, Lessee [Abstract] Operating Lease, Right-Of-Use Asset, Lessee [Abstract] Operating lease, right-of-use assets Operating Lease, Right-of-Use Asset Liabilities Operating Lease, Lease Liability, Lessee [Abstract] Operating Lease, Lease Liability, Lessee [Abstract] Operating lease liabilities, current Operating Lease, Liability, Current Operating lease liabilities, non-current Operating Lease, Liability, Noncurrent Total operating lease liabilities Operating Lease, Liability REVENUE RECOGNITION Revenue from Contract with Customer [Text Block] Schedule of Stock Option Expense and Activity Share-based Payment Arrangement, Activity [Table Text Block] Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Deferred commission costs, amortization period Capitalized Contract Cost, Amortization Period Contract with customer, revenue recognized Contract with Customer, Liability, Revenue Recognized subscription term Revenue, Subscription Term Revenue, Subscription Term Revenue, remaining performance obligation, amount Revenue, Remaining Performance Obligation, Amount RIGHT-OF-USE ASSETS AND LEASES Lessee, Operating Leases [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Number of reportable segments Number of Reportable Segments Income Tax Disclosure [Abstract] INCOME TAXES Income Tax Disclosure [Text Block] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Restricted Cash, Current And Other Accrued Liabilities Restricted Cash, Current And Other Accrued Liabilities [Member] Restricted Cash, Current And Other Accrued Liabilities [Member] Restricted Cash, Noncurrent And Other Liabilities, Noncurrent Restricted Cash, Noncurrent And Other Liabilities, Noncurrent [Member] Restricted Cash, Noncurrent And Other Liabilities, Noncurrent [Member] Other Accrued Liabilities, Current Other Accrued Liabilities, Current [Member] Other Accrued Liabilities, Current [Member] Other Noncurrent Liabilities Other Noncurrent Liabilities [Member] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Time-Based Restricted Stock Awards Time-Based Restricted Stock Awards [Member] Time-Based Restricted Stock Awards [Member] Performance-Based Restricted Stock Awards Performance-Based Restricted Stock Awards [Member] Performance-Based Restricted Stock Awards [Member] Business combination, consideration transferred Business Combination, Consideration Transferred Payments to acquire business Payments to Acquire Businesses, Gross Business combination, value of stock issued Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Cash held back to cover indemnity claims Business Combination, Indemnification Assets, Cash Held Back Business Combination, Indemnification Assets, Cash Held Back Equity held back to cover indemnity claims Business Combination, Indemnification Assets, Equity Held Back Business Combination, Indemnification Assets, Equity Held Back Stock awards granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Acquisition costs Business Combination, Acquisition Related Costs Earnings Per Share [Abstract] Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Income Statement [Abstract] Statement [Table] Statement [Table] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Service Service [Member] Product Product [Member] Statement [Line Items] Statement [Line Items] Total revenue Cost of revenue and operating expenses: Operating Expenses [Abstract] Cost of goods and services sold Cost of Goods and Services Sold Research and development Research and Development Expense Sales and marketing Selling and Marketing Expense General and administrative General and Administrative Expense Total operating expenses Operating Expenses Loss from operations Operating Income (Loss) Other (expense) income, net Nonoperating Income (Expense) Loss before provision for income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Net loss Net loss per share: Basic and diluted (in dollars per share) Earnings Per Share, Basic and Diluted Weighted-average common shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic and diluted (in shares) Weighted Average Number of Shares Outstanding, Basic and Diluted Fiscal Period Fiscal Period, Policy [Policy Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Reclassifications and Other Changes Reclassification, Policy [Policy Text Block] Recently Adopted Accounting Pronouncements, Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] NET LOSS PER SHARE Earnings Per Share [Text Block] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2016-02 Accounting Standards Update 2016-02 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Operating lease, right-of-use assets Present value of lease liabilities Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 2 Fair Value, Inputs, Level 2 [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] Debt instrument, fair value Debt Instrument, Fair Value Disclosure Contract Balances Contract with Customer, Asset and Liability [Table Text Block] CONVERTIBLE SENIOR NOTES AND CAPPED CALL Debt Disclosure [Text Block] Cash 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 Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Goodwill Goodwill Accounts payable 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 Total consideration Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net United States Americas [Member] International Europe [Member] Property and equipment, net Property, Plant and Equipment, Net FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of service revenue Cost Of Service Revenue [Member] Cost Of Service Revenue [Member] Research and development Research and Development Expense [Member] Sales and marketing Selling and Marketing Expense [Member] General and administrative General and Administrative Expense [Member] Stock-based compensation expense Share-based Payment Arrangement, Expense Commitments and Contingencies Disclosure [Abstract] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] BUSINESS COMBINATIONS Business Combination Disclosure [Text Block] Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Term of contract Lessee, Operating Lease, Term of Contract Renewal term Lessee, Operating Lease, Renewal Term Operating lease expense Operating Lease, Cost Amount of lease not yet commenced Lessee, Operating Lease, Lease Not Yet Commenced, Amount Lessee, Operating Lease, Lease Not Yet Commenced, Amount Area of real estate property Area of Real Estate Property Number of building stories Number of Building Stories Number of Building Stories Number of renewal terms Lessee, Operating Lease, Number Of Renewal Terms Lessee, Operating Lease, Number Of Renewal Terms Base rent Operating Leases, Rent Expense, Monthly Operating Leases, Rent Expense, Monthly Annual percentage increase in base rent Operating Leases, Rent Expense, Annual Rate Increase Operating Leases, Rent Expense, Annual Rate Increase Tenant improvements Lessee, Operating Lease, Tenant Improvement Allowance Lessee, Operating Lease, Tenant Improvement Allowance Security deposit Security Deposit Increase in operating lease right-of-use asset Increase (Decrease) In Operating Lease, Right-Of-Use Asset Increase (Decrease) In Operating Lease, Right-Of-Use Asset Increase in operating lease liability Increase (Decrease) In Operating Lease, Liability Increase (Decrease) In Operating Lease, Liability Stock Option Rollforward Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Stock options outstanding at the beginning of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Options granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Options exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Options canceled and forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Options outstanding at the end of the period (in shares) Weighted-average fair value of grants during the period (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Total intrinsic value of options exercised during the period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Weighted-average remaining recognition period at period-end (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Stock Award Rollforward Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] Stock awards outstanding at the beginning of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Stock awards vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Stock awards canceled and forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Stock awards outstanding at the end of the period (in shares) Weighted-average fair value of grants during the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted-average remaining recognition period at period-end (in years) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Total unrecognized compensation expense at period-end Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Convertible Debt Convertible Debt [Table Text Block] Interest Income and Interest Expense Disclosure Interest Income and Interest Expense Disclosure [Table Text Block] Remaining 2020 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2021 Lessee, Operating Lease, Liability, Payments, Due Year Two 2022 Lessee, Operating Lease, Liability, Payments, Due Year Three 2023 Lessee, Operating Lease, Liability, Payments, Due Year Four 2024 Lessee, Operating Lease, Liability, Payments, Due Year Five Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total lease payments Lessee, Operating Lease, Liability, Payments, Due Less: imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Less: lease incentives receivable Lease Incentive Receivable Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Schedule of Segment Reporting Information, by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] DESCRIPTION OF BUSINESS Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Goodwill [Roll Forward] Goodwill [Roll Forward] Balance at March 31, 2019 Additions due to acquisitions Goodwill, Acquired During Period Foreign currency translation Goodwill, Foreign Currency Translation Gain (Loss) Balance at December 31, 2019 Numerator: Earnings Per Share Reconciliation [Abstract] Net loss available to common stockholders Denominator: Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract] Common shares - basic and diluted (in shares) Net loss per share Earnings Per Share, Basic and Diluted [Abstract] Schedule of Recognized Identified Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Schedule of Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] Principal Debt Instrument, Unamortized Premium Debt Instrument, Unamortized Premium Unamortized debt discount Debt Instrument, Unamortized Discount Unamortized issuance costs Debt Issuance Costs, Net Net carrying amount Long-term Debt Contractual interest expense Interest Expense, Debt, Excluding Amortization Amortization of debt premium Amortization of Debt Premium Amortization of Debt Premium Amortization of debt discount Amortization of Debt Discount Amortization of Debt Discount Amortization of issuance costs Amortization of Debt Issuance Costs Total interest expense Interest Expense, Debt Statement of Financial Position [Abstract] ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash, current Restricted Cash, Current Short-term investments Short-term Investments Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Deferred sales commission costs Capitalized Contract Cost, Net, Current Other current assets Other Assets, Current Total current assets Assets, Current Property and equipment, net Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Long-term investments Long-term Investments Restricted cash, non-current Restricted Cash, Noncurrent Deferred sales commission costs, non-current Capitalized Contract Cost, Net, Noncurrent Other assets Other Assets, Noncurrent Total assets Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued compensation Employee-related Liabilities, Current Accrued taxes Accrued Income Taxes, Current Operating lease liabilities, current Deferred revenue Contract with Customer, Liability, Current Other accrued liabilities Other Accrued Liabilities, Current Total current liabilities Liabilities, Current Operating lease liabilities, non-current Convertible senior notes, net Long-term Debt, Excluding Current Maturities Other liabilities, non-current Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 8) Commitments and Contingencies Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Common stock 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 Stockholders' Equity Attributable to Parent Total liabilities and stockholders' equity Liabilities and Equity GEOGRAPHICAL INFORMATION Segment Reporting Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] ASU 2016-09 Accounting Standards Update 2016-09 [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Accumulated Deficit Retained Earnings [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance (shares) Shares, Issued Beginning balance Issuance of common stock under stock plans, less withholding (shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Issuance of common stock under stock plans, less withholding Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Stock-based compensation expense APIC, Share-based Payment Arrangement, Increase for Cost Recognition Equity component of convertible senior notes, net of issuance costs Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt Issuance of common stock related to acquisitions (shares) Stock Issued During Period, Shares, Acquisitions Issuance of common stock related to acquisitions Stock Issued During Period, Value, Acquisitions Unrealized investment gain Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Foreign currency translation adjustment Adjustment from adoption of ASU 2016-9 Cumulative Effect of New Accounting Principle in Period of Adoption Ending balance (shares) Ending balance Accounts receivable, net Contract assets - current Contract with Customer, Asset, Net, Current Contract assets - non-current Contract with Customer, Asset, Net, Noncurrent Deferred revenue - current Deferred revenue - non-current Contract with Customer, Liability, Noncurrent Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net loss 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] Depreciation Depreciation Amortization of intangible assets Amortization of Intangible Assets Amortization of capitalized software Capitalized Computer Software, Amortization Amortization of debt discount and issuance costs Amortization of Debt Issuance Costs and Discounts Amortization of deferred sales commission costs Amortization of Deferred Sales Commissions Operating lease expense, net of accretion Operating Lease Expense, Net Of Accretion Operating Lease Expense, Net Of Accretion Non-cash lease expenses Lease, Non-Cash Lease Expense Lease, Non-Cash Lease Expense Stock-based compensation Share-based Payment Arrangement, Noncash Expense Other Other Operating Activities, Cash Flow Statement Changes in assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable, net Increase (Decrease) in Accounts Receivable Deferred sales commission costs Increase (Decrease) in Deferred Charges Other current and non-current assets Increase (Decrease) in Other Operating Assets Accounts payable and accruals Increase (Decrease) in Accounts Payable and Accrued Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Purchase of businesses Payments to Acquire Businesses, Net of Cash Acquired Capitalized software development costs Payments for Software Proceeds from maturities of investments Proceeds from Sale, Maturity and Collection of Short-term Investments Proceeds from sales of investments Proceeds from Sale and Maturity of Marketable Securities Purchases of investments Payments to Acquire Marketable Securities Net cash (used in) provided by investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Finance lease payments Finance Lease, Principal Payments Finance lease payments Repayments of Long-term Capital Lease Obligations Tax-related withholding of common stock Payment, Tax Withholding, Share-based Payment Arrangement Proceeds from issuance of common stock under employee stock plans Proceeds from Stock Plans Net proceeds from issuance of convertible senior notes Proceeds from Convertible Debt Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Effect of exchange rate changes on cash Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Net decrease in cash and 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 the beginning of the period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, cash equivalents, and restricted cash at the end of the period Supplemental cash flow information Supplemental Cash Flow Information [Abstract] Income taxes paid Income Taxes Paid Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activities Right of use assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, remaining performance obligation, expected timing of satisfaction, period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Cash and Cash Equivalents Cash and Cash Equivalents [Member] Short-term Investments Short-term Investments [Member] Long-term Investments Long-term Investments [Member] Long-term Investments [Member] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Cash Cash [Member] Money market funds Money Market Funds [Member] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Treasury securities US Treasury Securities [Member] Corporate bonds Corporate Debt Securities [Member] Commercial paper Commercial Paper [Member] Municipal securities US States and Political Subdivisions Debt Securities [Member] Asset backed securities Asset-backed Securities [Member] Agency bonds Other Debt Obligations [Member] Level 1 Fair Value, Inputs, Level 1 [Member] Cash and cash equivalents Cash and cash equivalents, fair value Cash and Cash Equivalents, Fair Value Disclosure Amortized cost Debt Securities, Available-for-sale, Amortized Cost Accumulated gross unrealized gain, before tax Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Accumulated gross unrealized loss, before tax Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Debt securities, available-for-sale Debt Securities, Available-for-sale Cash, cash equivalents and debt securities available-for-sale, amortized cost Cash, Cash Equivalents and Debt Securities Available-for-sale, Amortized Cost Cash, Cash Equivalents and Debt Securities Available-for-sale Cash, cash equivalents and debt securities available-for-sale Cash, Cash Equivalents and Debt Securities Available-for-sale Cash, Cash Equivalents and Debt Securities Available-for-sale 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] Stock options Share-based Payment Arrangement, Option [Member] Stock awards Restricted Stock [Member] Contingently issuable shares (hold-back shares) Performance Shares [Member] Potential shares to be issued from ESPP Employee Stock [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Number of anti-dilutive shares (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets, Major Class Name [Domain] Developed technology Patented Technology [Member] Customer relationships Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Gross Carrying Amount Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization