Earnings Per Share [Abstract] 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] Time-vesting Shares [Member] Time-vesting Shares [Member] Time-vesting Shares [Member] Performance Shares [Member] Performance Shares [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive securities excluded from computation of earnings per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Loss Per Share (EPS) Earnings Per Share [Text Block] Receivables [Abstract] Accounts and Other Receivables, Net Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Document and Entity Information [Abstract] Document and entity information. 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 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] Restricted Stock [Member] Restricted Stock [Member] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Performance-based Vesting [Member] Performance-based Vesting [Member] Performance-based Vesting [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Outstanding beginning of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Outstanding end of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Outstanding beginning of the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment 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Employee Stock Option [Member] Employee Stock Option [Member] Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [Member] Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected life Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Weighted average Black-Scholes value of options granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Expected average period options will be exercised after vesting Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Average Period Options will be Exercised After Vesting Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Average Period Options will be Exercised After Vesting Estimated forfeiture rate Share-based Compensation Arrangement by Share-based Payment Award, Estimated Forfeiture Rate Share-based Compensation Arrangement by Share-based Payment Award, Estimated Forfeiture Rate Award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Income Statement [Abstract] Revenue: Revenues [Abstract] Product Sales Revenue, Goods, Net Service Sales Revenue, Services, Net Total revenue Revenues Cost of revenue: Cost of Revenue [Abstract] Cost of product revenue Cost of Goods Sold Cost of service revenue Cost of Services Total cost of revenue Cost of Goods and Services Sold Gross profit Gross Profit Operating expenses: Operating Expenses [Abstract] Research and development, net Research 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Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income Comprehensive Income (Loss) Note [Text Block] Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Product [Member] Product [Member] Service [Member] Service [Member] Service [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of Sales [Member] Cost of Sales [Member] Research and Development Expense [Member] Research and Development Expense [Member] Selling and Marketing Expense [Member] Selling and Marketing Expense [Member] General and Administrative Expense [Member] General and Administrative Expense [Member] Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Abstract] Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Abstract] Unrecognized compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized compensation expense period of recognition Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Allocated Share-based Compensation Expense Allocated Share-based Compensation Expense Market price offering date Share Based Compensation Arrangement By Share Based Payment Award Market Price Offering Date Share Based Compensation Arrangement By Share Based Payment Award Market Price Offering Date Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] 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] Cash and cash equivalents and restricted cash Cash and Cash Equivalents, Fair Value Disclosure Available-for-sale investments Investments, Fair Value Disclosure Foreign currency exchange contracts Foreign Currency Contract, Asset, Fair Value Disclosure Assets measured at fair value at March 31, 2017 Assets, Fair Value Disclosure Foreign currency exchange contracts Foreign Currency Contracts, Liability, Fair Value Disclosure Liabilities measured at fair value at March 31, 2017 Financial and Nonfinancial Liabilities, Fair Value Disclosure Leases [Abstract] Total minimum lease payments to be received Capital Leases, Net Investment in Sales Type Leases, Minimum Payments to be Received Less: executory costs Capital Leases, Net Investment in Sales Type Leases, Executory Costs Net minimum lease payments receivable Capital Leases, Net Investment in Sales Type Leases, Minimum Payments to be Received, Less Executory Costs Capital Leases, Net Investment in Sales Type Leases, Minimum Payments to be Received, Less Executory Costs Less: unearned income Capital Leases, Net Investment in Sales Type Leases, Deferred Income Net investment in sales-type lease Capital Leases, Net Investment in Sales Type Leases Less: long-term investment in sales-type lease Capital Leases, Lessor Balance Sheet, Net Investment in Direct Financing and Sales Type Leases, Noncurrent Investment in sales-type lease included in accounts and other receivables Capital Leases, Lessor Balance Sheet, Net Investment in Sales Type Leases, Current 2017 (less than 1 year) Capital Leases, Future Minimum Payments Receivable, Next Twelve Months 2018 Capital Leases, Future Minimum Payments, Receivable in Two Years 2019 Capital Leases, Future Minimum Payments, Receivable in Three Years 2020 Capital Leases, Future Minimum Payments, Receivable in Four Years Total minimum lease payments to be received Capital Leases, Future Minimum Payments Receivable Sales-type Lease Capital Leases in Financial Statements of Lessor Disclosure [Text Block] Accounting Policies [Abstract] Product delivery period Product Delivery Period Product delivery period. Maintenance services period Maintenance Services Period Maintenance services period. 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 Restricted Cash and Cash Equivalents, Current Short-term investments Available-for-sale Securities, Current Accounts and other receivables, net Accounts, Notes, Loans and Financing Receivable, Net, Current Inventory Inventory, Net Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Assets, Noncurrent [Abstract] Assets, Noncurrent [Abstract] Long-term restricted cash Restricted Cash and Cash Equivalents, Noncurrent Long-term investment in sales-type lease, net Property and equipment, net Property, Plant and Equipment, Net Service spares, net Inventory, Parts and Components, Net of Reserves Goodwill Goodwill Intangible assets other than goodwill, net Intangible Assets, Net (Excluding Goodwill) Deferred tax assets Other non-current assets Other Assets, Noncurrent TOTAL ASSETS Assets LIABILITIES AND SHAREHOLDERS’ EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued payroll and related expenses Employee-related Liabilities, Current Other accrued liabilities Accrued Liabilities, Current Deferred revenue Deferred Revenue, Current Total current liabilities Liabilities, Current Liabilities, Noncurrent [Abstract] Liabilities, Noncurrent [Abstract] Long-term deferred revenue Deferred Revenue, Noncurrent Other non-current liabilities Other Liabilities, Noncurrent TOTAL LIABILITIES Liabilities Shareholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock — Authorized and undesignated, 5,000,000 shares; no shares issued or outstanding Preferred Stock, Value, Issued Common stock and additional paid-in capital, par value $.01 per share — Authorized, 75,000,000 shares; issued and outstanding 40,300,399 and 40,757,458 shares, respectively Common Stock, Value, Issued Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated deficit Retained Earnings (Accumulated Deficit) TOTAL SHAREHOLDERS’ EQUITY Stockholders' Equity Attributable to Parent TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY Liabilities and Equity Deferred Revenue Disclosure [Abstract] Deferred Revenue Deferred Revenue, by Arrangement, Disclosure [Table Text Block] Effective Tax Rates Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Segment Reporting [Abstract] Information on Operating Segments Schedule of Segment Reporting Information, by Segment [Table Text Block] Revenue by Geographic Location Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block] Commitments and Contingencies Disclosure [Abstract] Contingencies Commitments and Contingencies Disclosure [Text Block] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Government Contracts Concentration Risk [Member] Government Contracts Concentration Risk [Member] Non-US Government Customers [Member] Non-US Government Customers [Member] Non-US government customers. Billing Status, Type [Axis] Billing Status, Type [Axis] Receivables Billing Status [Domain] Receivables Billing Status [Domain] Unbilled Revenues [Member] Unbilled Revenues [Member] Receivable Type [Axis] Receivable Type [Axis] Receivable [Domain] Receivable [Domain] Trade Accounts Receivable [Member] Trade Accounts Receivable [Member] Unbilled Receivables [Member] Unbilled Receivables [Member] Unbilled Receivables [Member] Advance Billings [Member] Advance Billings [Member] Advance billings. Short-Term Tnvestment In Sales-Type Lease [Member] Financing Receivable [Member] Other Receivables [Member] Other Receivables [Member] Other receivables. Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Accounts Receivable [Member] Accounts Receivable [Member] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts and other receivables, gross Accounts Receivable, Gross, Current Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current Accounts and other receivables, net Concentration risk, percent Concentration Risk, Percent Concentration Risk, Percent Inventory Disclosure [Abstract] Inventory Inventory Disclosure [Text Block] Statement of Cash Flows [Abstract] Operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net loss Adjustments to reconcile net 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 Share-based compensation expense Share-based Compensation Deferred income taxes Deferred Income Tax Expense (Benefit) Other Other Noncash Income (Expense) Cash provided (used) due to changes in operating assets and liabilities: Increase (Decrease) in Operating Assets [Abstract] Accounts and other receivables Increase (Decrease) in Accounts and Other Receivables Long-term investment in sales-type lease, net Increase (Decrease) in Leasing Receivables Inventory Increase (Decrease) in Inventories Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued payroll and related expenses and other liabilities Increase (Decrease) in Accrued Salaries Deferred revenue Increase (Decrease) in Deferred Revenue Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Sales/maturities of available-for-sale investments Proceeds from Sale and Maturity of Available-for-sale Securities Purchases of available-for-sale investments Payments to Acquire Available-for-sale Securities Change in restricted cash Increase (Decrease) in Restricted Cash Purchases 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 Financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from issuance of common stock through employee stock purchase plan Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Purchase of employee restricted shares to fund related statutory tax withholding Payments Related to Tax Withholding for Share-based Compensation Proceeds from exercises of stock options Proceeds from Stock Options Exercised Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Effect of foreign exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents Net increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents: Cash and Cash Equivalents, at Carrying Value, Including Discontinued Operations [Abstract] Beginning of period End of period Supplemental disclosure of cash flow information: Supplemental Cash Flow Information [Abstract] Cash paid for income taxes Income Taxes Paid, Net Non-cash investing and financing activities: Other Noncash Investing and Financing Items [Abstract] Inventory transfers to fixed assets and service spares Inventory Transfers to Fixed Assets and Service Inventory Inventory transfers to fixed assets and service inventory. Investments, Debt and Equity Securities [Abstract] Cost Available-for-sale Securities, Amortized Cost Basis Unrealized gains (losses) Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax Fair Value Available-for-sale Securities Fair Value Assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Stock Option Activity Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Restricted Stock Activity Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Allocation of Share-Based Compensation Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] Principles of Consolidation Consolidation, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Deferred Revenue Deferred Revenue Disclosure [Text Block] Investments Available-for-sale Securities [Table Text Block] Basis of Presentation Basis of Presentation and Significant Accounting Policies [Text Block] Share-Based Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Investments Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Segment Information Segment Reporting Disclosure [Text Block] Reclassification from Accumulated Other Comprehensive Income (Loss) Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Statement of Comprehensive Income [Abstract] Net loss Other comprehensive income (loss), net of tax: Unrealized gain on available-for-sale 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 Unrealized gain (loss) on cash flow hedges Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Reclassification adjustments on cash flow hedges included in net loss Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Supercomputing [Member] Supercomputing [Member] Supercomputing [Member] Storage and Data Management [Member] Storage and Data Management [Member] Storage and Data Management [Member] Maintenance and Support [Member] Maintenance and Support [Member] Maintenance and support. Other Segments [Member] Other Segments [Member] Intersegment Eliminations [Member] Intersegment Eliminations [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Total gross profit Inventory, Current [Table] Inventory, Current [Table] Finished Goods Inventory [Member] Finished Goods Inventory [Member] Finished Goods Inventory [Member] Inventory [Axis] Inventory [Axis] Inventory [Domain] Inventory [Domain] Located at Customer Sites [Member] Located at Customer Sites [Member] Located at Customer Sites [Member] Inventory [Line Items] Inventory [Line Items] Components and subassemblies Inventory, Raw Materials and Supplies, Net of Reserves Work in process Inventory, Work in Process, Net of Reserves Finished goods Inventory, Finished Goods, Net of Reserves Total Inventory written off Inventory Write-down Components of the Net Investment in the Sales-type Lease Components of the Net Investment in the Sales-type Lease [Table Text Block] [Table Text Block] for Components of the Net Investment in the Sales-type Lease [Table] Minimum Lease Payments to be Received for Each of the Next Five Fiscal Years Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block] Inventory Schedule of Inventory, Current [Table Text Block] Accounts and Other Receivables, Net Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Civil Action No. 2:15-cv-1554 [Member] Civil Action No. 2:15-cv-1554 [Member] Civil Action No. 2:15-cv-1554 [Member] Civil Action No. 2:16-cv-423 [Member] Civil Action No. 2:16-cv-423 [Member] Civil Action No. 2:16-cv-423 [Member] Litigation Status [Axis] Litigation Status [Axis] Litigation Status [Domain] Litigation Status [Domain] Pending Litigation [Member] Pending Litigation [Member] Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Patents Related to Company's Computer Hardware [Member] Patents Related to Company's Computer Hardware [Member] Patents Related to Company's Computer Hardware [Member] Patents Related to Third Party's Computer Software [Member] Patents Related to Third Party's Computer Software [Member] Patents Related to Third Party's Computer Software [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Loss contingency, patents allegedly infringed, number Loss Contingency, Patents Allegedly Infringed, Number Loss contingency, pending lawsuit, number Loss Contingency, Pending Lawsuit, Number Loss Contingency, Pending Lawsuit, Number New Accounting Pronouncements and Changes in Accounting Principles [Abstract] New Accounting Pronouncements Description of New Accounting Pronouncements Not yet Adopted [Text Block] Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Preferred stock, shares outstanding Preferred Stock, Shares Outstanding Common stock and additional paid-in capital, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock and additional paid-in capital, shares authorized Common Stock, Shares Authorized Common stock and additional paid-in capital, shares issued Common Stock, Shares, Issued Common stock and additional paid-in capital, shares outstanding Common Stock, Shares, Outstanding Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Accumulated Net Unrealized Investment Gain (Loss) [Member] Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Accumulated Translation Adjustment [Member] Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Gross of tax reclassifications Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax Net of tax reclassifications Beginning balance Current-period change, net of tax Ending balance Income tax expense (benefit) associated with current-period change Other Comprehensive Income (Loss), Tax Company's Financial Assets and Liabilities Measured at Fair Value and the Hierarchy of the Valuation Inputs Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Table Text Block] Schedule of Notional Amounts of Outstanding Derivative Positions Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block] Fair Values of Derivative Instruments and Balance Sheet Location Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding beginning of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Grants (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Exercises (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Canceled and forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Outstanding end of the period (in shares) Exercisable end of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Available for grant end of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant 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] Outstanding beginning of the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Grants (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercises (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Canceled and forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Outstanding end of the period (in dollars per share) Exercisable end of the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Outstanding, weighted average remaining contractual term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Exercisable, weighted average remaining contractual term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Outstanding, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Exercisable, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Revenue [Member] Revenue [Member] Revenue [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] UNITED STATES UNITED STATES Non-US Non-US [Member] Australia and the UK Australia and the UK [Member] Australia and the UK [Member] Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Product revenue Service revenue Total revenue Concentration risk, percentage Concentration Risk, Percentage Deferred Revenue Arrangement, by Type [Table] Deferred Revenue Arrangement, by Type [Table] Deferred Revenue [Member] Deferred Revenue [Member] Deferred Revenue [Member] Deferred Revenue Arrangement [Line Items] Deferred Revenue Arrangement [Line Items] Total deferred revenue Deferred Revenue Deferred revenue in current liabilities