Statement of Comprehensive Income [Abstract] Net income (loss) Net Income (Loss) Attributable to Parent Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Foreign currency translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent 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] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] PSU Performance Restricted Stock Units [Member] Performance Restricted Stock Units [Member] Market performance shares Performance Shares [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Awarded (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Service period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Number of annual tranches Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Annual Tranches Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Annual Tranches Maximum potential to vest (as a percentage) Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Maximum Potential To Vest Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Maximum Potential To Vest Maximum potential to vest (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other than Options, Maximum Number Of Shares To Vest Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other than Options, Maximum Number Of Shares To Vest Weighted average fair value, units awarded (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 Restricted stock units Restricted Stock Units (RSUs) [Member] Commitments and Contingencies Disclosure [Abstract] Loss Contingencies [Table] Loss Contingencies [Table] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Realtime Realtime Data LLC dba IXO [Member] Realtime Data LLC dba IXO [Member] Litigation Status [Axis] Litigation Status [Axis] Litigation Status [Domain] Litigation Status [Domain] Pending Settled Litigation [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Number of patents involved in alleged infringement Loss Contingency, Patents Allegedly Infringed, Number General and administrative expense accrued in connection to litigation settlement Gain (Loss) Related to Litigation Settlement Restructuring and Related Activities [Abstract] Restructuring Restructuring and Related Activities Disclosure [Text Block] Accounting Policies [Abstract] Concentration Risk [Table] Concentration Risk [Table] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Customer Concentration Risk Customer Concentration Risk [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Arrow Arrow [Member] Arrow [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Revenue Sales Revenue, Net [Member] Accounts receivable Accounts Receivable [Member] Concentration Risk [Line Items] Concentration Risk [Line Items] Concentration risk percentage Concentration Risk, Percentage Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Lease abandonment charges Contract Termination [Member] Severance & payroll related charges Employee Severance [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Balance at March 31, 2018 Restructuring Reserve Restructuring charges Restructuring Charges Payments Payments for Restructuring Accrual reversals Restructuring Reserve, Accrual Adjustment Balance at December 31, 2018 Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Concentration of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Revenue Revenue from Contract with Customer [Policy Text Block] Earnings Per Share [Abstract] Antidilutive securities excluded from computation (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Statement of Cash Flows [Abstract] Cash flows from operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Net Income (loss) 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 Noncash stock-based compensation Share-based Compensation Deferred income taxes Deferred Income Tax Expense (Benefit) Equity in loss of affiliate Income (Loss) from Equity Method Investments Amortization of deferred commissions cost Amortization of Deferred Sales Commissions Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Trade accounts receivable Increase (Decrease) in Receivables Other current assets and Other assets Increase (Decrease) in Other Operating Assets Deferred commissions cost Increase (Decrease) In Deferred Sales Commissions Increase (Decrease) in Deferred Sales Commissions Accounts payable Increase (Decrease) in Accounts Payable Accrued liabilities Increase (Decrease) in Accrued Liabilities Deferred revenue Increase (Decrease) in Contract with Customer, Liability Other liabilities Increase (Decrease) in Other Operating Liabilities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Purchase of short-term investments Payments to Acquire Short-term Investments Proceeds from maturity of short-term investments Proceeds from Sale of Short-term Investments Purchase of property and equipment Payments to Acquire Property, Plant, and Equipment Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Repurchase of common stock Payments for Repurchase of Common Stock Proceeds from stock-based compensation plans Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Effects of exchange rate — changes in cash Effect of Exchange Rate on Cash and Cash Equivalents Net decrease in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Hierarchy Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 Fair Value, Inputs, Level 1 [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Short-term investments Debt Securities, Held-to-maturity, Fair Value Equity [Abstract] Capitalization Capitalization [Text Block] Entities disclosure for capitalization. Number of Awards Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Non-vested (in shares) as of March 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Non-vested (in shares) as of December 31, 2018 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] Non-vested (in dollars per share) as of March 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Awarded (in dollars per share) 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 Forfeited (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 Non-vested (in dollars per share) as of December 31, 2018 Income Statement [Abstract] Statement [Table] Statement [Table] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Software and products Software And Products [Member] Software And Products [Member] Services Service [Member] Statement [Line Items] Statement [Line Items] Revenues: Revenue from Contract with Customer [Abstract] Total revenues Revenue from Contract with Customer, Excluding Assessed Tax Cost of revenues: Cost of Goods and Services Sold [Abstract] Total cost of revenues Cost of Goods and Services Sold Gross margin Gross Profit Operating expenses: Operating Expenses [Abstract] Sales and marketing Selling and Marketing Expense Research and development Research and Development Expense General and administrative General and Administrative Expense Restructuring Restructuring and Related Cost, Incurred Cost Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Total operating expenses Operating Expenses Income (loss) from operations Operating Income (Loss) Interest income Investment Income, Interest Interest expense Interest and Debt Expense Equity in loss of affiliate Income (loss) before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income tax expense (benefit) Income Tax Expense (Benefit) Net income (loss) Net income (loss) per common share: Basic (in dollars per share) Earnings Per Share, Basic Diluted (in dollars per share) Earnings Per Share, Diluted Weighted average common shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Stock Plans Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Software and Products Revenue Software [Member] Software [Member] Customer Support Revenue Customer Support [Member] Customer Support [Member] Professional Services Professional Services [Member] Professional Services [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] Americas Americas [Member] EMEA EMEA [Member] APAC Asia Pacific [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] 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] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs, by Report Line Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of services revenue Cost Of Services Revenue [Member] Cost of services revenue Member. Sales and marketing Selling and Marketing Expense [Member] Research and development Research and Development Expense [Member] General and administrative General and Administrative Expense [Member] Restructuring 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] Stock-based compensation expense Financial Assets Measured at Fair Value Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Table Text Block] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Contract with Customer, Asset and Liability Contract with Customer, Asset and Liability [Table Text Block] Stock-Based Compensation Expense Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] Schedule of Stock Option Activity Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Restricted Stock Unit Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Income Tax Disclosure [Abstract] Deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Tax cuts and jobs act, transition tax Tax Cuts And Jobs Act, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense Tax Cuts And Jobs Act, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense Total intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Statement of Financial Position [Abstract] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Restructuring and Related Costs Restructuring and Related Costs [Table Text Block] Sources of primary revenue Sources Of Primary Revenue The number of sources of revenue in a typical sales agreement. Customer support agreement term Customer Support Agreement The typical length of Customer Support Agreements. Number of operating segments Number of Operating Segments Revenue recognized in period, included in opening deferred revenue balance Contract with Customer, Liability, Revenue Recognized 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 [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue expected to be recognized from remaining performance obligations Revenue, Remaining Performance Obligation, Amount Revenue Revenue from Contract with Customer [Text Block] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Common stock repurchase program Common Stock Repurchase Program [Member] Common Stock Repurchase Program [Member] Class of Stock [Line Items] Class of Stock [Line Items] Remaining amount available under share repurchase program Stock Repurchase Program, Remaining Authorized Repurchase Amount Document And Entity Information [Abstract] Document and Entity Information Abstract. Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Emerging Growth Company Entity Emerging Growth Company Entity Small Business Entity Small Business Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2016 Incentive Plan 2016 Incentive Plan [Member] 2016 Incentive Plan [Member] Stock options and restricted stock units Stock Options and Restricted Stock Units [Member] Stock Options and Restricted Stock Units [Member] Maximum number of shares of common stock that may be delivered under plan (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Addition shares authorized (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Unrecognized stock-based compensation expense, net of estimated forfeitures Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Weighted average period awards are expected to be recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Net Income per Common Share Earnings Per Share [Text Block] Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Number of Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding (in shares) as of March 31, 2018 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 forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Options expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period Outstanding (in shares) as of December 31, 2018 Exercisable (in shares) as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted- Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Outstanding (in dollars per share) as of March 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Options granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Options exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Options forfeited (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Options expired (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Outstanding (in dollars per share) as of December 31, 2018 Exercisable (in dollars per share) as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Share Based Compensation Arrangement By Share Based Payment Award Other Than Options Weighted Average Remaining Contractual Term [Abstract] Share based Compensation Arrangement by Share based Payment Award, Other than Options, Weighted Average Remaining Contractual Term [Abstract] Outstanding as of December 31 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Exercisable as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Share Based Compensation Arrangement By Share Based Payment Award Options Aggregate Intrinsic Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract] Outstanding as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Exercisable as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Statement of Stockholders' Equity [Abstract] 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 Deficit Retained Earnings [Member] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [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] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance (in shares) Shares, Outstanding Beginning balance Stockholders' Equity Attributable to Parent Cumulative Effect of Adoption of ASU 2016-09 Cumulative Effect of New Accounting Principle in Period of Adoption Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Share issuances related to stock-based compensation (in shares) Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Share issuances related to stock-based compensation Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Repurchase of common stock (in shares) Stock Repurchased During Period, Shares Repurchase of common stock Stock Repurchased During Period, Value Other comprehensive income (loss) Ending balance (in shares) Ending balance ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Short-term investments Debt Securities, Held-to-maturity, Current Trade accounts receivable Receivables, Net, Current Other current assets Other Assets, Current Total current assets Assets, Current Property and equipment, net Property, Plant and Equipment, Net Deferred commissions cost 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 liabilities Accrued Liabilities, Current Deferred revenue Contract with Customer, Liability, Current Total current liabilities Liabilities, Current Deferred revenue, less current portion Contract with Customer, Liability, Noncurrent Deferred tax liabilities, net Deferred Tax Liabilities, Net Other liabilities Other Liabilities, Noncurrent Commitments and contingencies Commitments and Contingencies Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.01 par value: 50,000 shares authorized, no shares issued and outstanding at December 31, 2018 and March 31, 2018 Preferred Stock, Value, Issued Common stock, $0.01 par value: 250,000 shares authorized, 45,799 shares and 45,118 shares issued and outstanding at December 31, 2018 and March 31, 2018, respectively Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock Accumulated deficit Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity Total liabilities and stockholders’ equity Liabilities and Equity Accounts Receivable [Roll Forward] Accounts Receivable [Roll Forward] Accounts Receivable [Roll Forward] Opening Balance as of March 31, 2018 Accounts Receivable, Net Increase/(decrease), net Increase (Decrease) in Accounts Receivable Ending Balance as of December 31, 2018 Unbilled Receivable (current) [Roll Forward] Contract With Customer, Asset, Net, Current [Roll Forward] Contract With Customer, Asset, Net, Current [Roll Forward] Opening Balance as of March 31, 2018 Unbilled Receivables, Current Increase/(decrease), net Increase (Decrease) In Unbilled Receivables, Current Increase (Decrease) in Unbilled Receivables, Current Ending Balance as of December 31, 2018 Unbilled Receivable (long-term) [Roll Forward] Contract With Customer, Asset, Net, Noncurrent [Roll Forward] Contract With Customer, Asset, Net, Noncurrent [Roll Forward] Opening Balance as of March 31, 2018 Unbilled Receivables, Noncurrent Unbilled Receivables, Noncurrent Increase/(decrease), net Increase (Decrease) In Unbilled Receivables, Noncurrent Increase (Decrease) In Unbilled Receivables, Noncurrent Ending Balance as of December 31, 2018 Deferred Revenue (current) [Roll Forward] Contract With Customer, Liability, Current [Roll Forward] Contract with Customer, Liability, Current [Roll Forward] Opening Balance as of March 31, 2018 Increase/(decrease), net Contract With Customer, Liability, Current, Increase (Decrease) Contract With Customer, Liability, Current, Increase (Decrease) Ending Balance as of December 31, 2018 Deferred Revenue (long-term) [Roll Forward] Contract With Customer, Liability, Noncurrent [Roll Forward] Contract With Customer, Liability, Noncurrent [Roll Forward] Opening Balance as of March 31, 2018 Increase/(decrease), net Contract With Customer, Liability, Noncurrent, Increase (Decrease) Contract With Customer, Liability, Noncurrent, Increase (Decrease) Ending Balance as of December 31, 2018 Stock-Based Compensation Stock-Based Compensation [Member] Stock-Based Compensation [Member] Restructuring charges incurred Software, licenses Software, Licenses [Member] Software, Licenses [Member] Software, appliances Software, Appliances [Member] Software, Appliances [Member] Professional Services, other Professional Services, Other [Member] Professional Services, Other [Member] Professional Services, education services Professional Services, Education Services [Member] Professional Services, Education Services [Member] Performance obligation, expected payment terms Revenue, Performance Obligation, Description Of Payment Terms, Period Revenue, Performance Obligation, Description Of Payment Terms, Period Income Taxes Income Tax Disclosure [Text Block]