DEI [Abstract] DEI [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Entity Well Known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Finite-Lived and Indefinite-Lived Intangible Assets by Major Class 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] Income Statement [Abstract] Statement [Table] Statement [Table] Statement, Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Statement [Line Items] Statement [Line Items] REVENUE: Revenue, Net [Abstract] Product Sales Revenue, Goods, Net Service Sales Revenue, Services, Net Total revenue Revenue, Net COST OF REVENUE: Cost of Goods and Services Sold [Abstract] Product Cost of Goods Sold Service Cost of Services Total cost of revenue Cost of Goods and Services Sold GROSS PROFIT: Gross Profit [Abstract] Product Product Gross Profit Products Gross profit is the aggregate revenue less cost of goods sold directly attributable to the revenue generation activity. Service Services Gross Profit Service Gross Profit is the aggregate revenue less cost of services sold or operating expenses directly attributable to the revenue generation activity. Total gross profit Gross Profit OPERATING EXPENSES: Operating Expenses [Abstract] Research and development Research and Development Expense Sales and marketing Selling and Marketing Expense General and administrative General and Administrative Expense Restructuring charges Restructuring Charges Total operating expenses Operating Expenses OPERATING INCOME Operating Income (Loss) INTEREST INCOME Investment Income, Net OTHER INCOME (EXPENSE)—NET Other Nonoperating Income (Expense) INCOME BEFORE INCOME TAXES Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest BENEFIT FROM INCOME TAXES Income Tax Expense (Benefit) NET INCOME Net Income (Loss) Attributable to Parent Net income per share (Note 8): Earnings Per Share [Abstract] Basic (in dollars per share) Earnings Per Share, Basic Diluted (in dollars per share) Earnings Per Share, Diluted Weighted-average 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 Segment Reporting [Abstract] SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Share-based Compensation, Restricted Stock Units Award Activity Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block] Schedule of Share-based Compensation, Shares Withheld for Taxes Schedule of Share-based Compensation, Shares Withheld for Taxes [Table Text Block] Schedule of Share-based Compensation, Shares Withheld for Taxes [Table Text Block] Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions And Allocation of Recognized Period Costs [Table Text Block] Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed. Schedule of Share-based Compensation, Stock Options, Activity Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Share-based Compensation, Stock Options, Activity, Additional Information Schedule of Share-based Compensation, Stock Options, Activity, Additional Information [Table Text Block] Schedule of Share-based Compensation, Stock Options, Activity, Additional Information Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block] Schedule of Share-based Payment Award Employee Stock Purchase Plan Additional Information Schedule of Share based Payment Award Employee Stock Purchase Plan Additional Information [Table Text Block] Schedule of Share based Payment Award Employee Stock Purchase Plan Additional Information [Table Text Block] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type [Table Text Block] Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type [Table Text Block] Income Tax Benefit from Stock Option Plans Income Tax Benefit from Stock Option Plans [Table Text Block] Income Tax Benefit from Stock Option Plans [Table Text Block] Inventory Disclosure [Abstract] INVENTORY Inventory Disclosure [Text Block] Property, Plant and Equipment [Abstract] Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment by Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Building and building improvements [Member] Building and Building Improvements [Member] Computer equipment and software [Member] Computer Equipment [Member] Land [Member] Land [Member] Leasehold improvements and tooling [Member] Leaseholds and Leasehold Improvements [Member] Evaluation units [Member] Evaluation Units [Member] Evaluation units [Member] Furniture and fixtures [Member] Furniture and Fixtures [Member] Construction-in-progress [Member] Construction in Progress [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Net, by Type [Abstract] Property, Plant and Equipment, Net, by Type [Abstract] Total property and equipment Property, Plant and Equipment, Gross Less: accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment - net Property, Plant and Equipment, Net Depreciation expense Depreciation Commitments and Contingencies Disclosure [Abstract] Contractual Obligation, Fiscal Year Maturity Schedule Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block] Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Stock-based compensation Share-based Compensation Amortization of deferred contract costs Capitalized Contract Cost, Amortization Depreciation and amortization Depreciation, Depletion and Amortization Other non-cash items—net Other Noncash Income (Expense) Amortization of investment premiums Accretion (Amortization) of Discounts and Premiums, Investments Changes in operating assets and liabilities: Increase (Decrease) in Other Operating Assets and Liabilities, Net [Abstract] Accounts receivable—net Increase (Decrease) in Accounts Receivable Inventory Increase (Decrease) in Inventories Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Deferred contract costs Increase (Decrease) in Contract Receivables, Net Deferred tax assets Increase (Decrease) in Deferred Income Taxes Other assets Increase (Decrease) in Other Operating Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued liabilities Increase (Decrease) in Accrued Liabilities Accrued payroll and compensation Increase (Decrease) in Employee Related Liabilities Other liabilities Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Income taxes payable Increase (Decrease) in Income Taxes Payable 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] Purchases of investments Payments to Acquire Investments Sales of investments Proceeds from Sale of Available-for-sale Securities Maturities of investments Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Purchases of property and equipment Payments to Acquire Productive Assets 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 and retirement of common stock Payments for Repurchase of Common Stock Proceeds from issuance of common stock Proceeds from Issuance of Common Stock Taxes paid related to net share settlement of equity awards Payments Related to Tax Withholding for Share-based Compensation Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities NET INCREASE IN CASH AND CASH EQUIVALENTS Cash and Cash Equivalents, Period Increase (Decrease) CASH AND CASH EQUIVALENTS—Beginning of period Cash and Cash Equivalents, at Carrying Value CASH AND CASH EQUIVALENTS—End of period NON-CASH INVESTING AND FINANCING ACTIVITIES: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Transfers of evaluation units from inventory to property and equipment Transfers of Evaluation Units from Inventory to Property and Equipment Transfers of Evaluation Units from Inventory to Property and Equipment Liability for purchase of property and equipment and asset retirement obligations Capital Expenditures Incurred but Not yet Paid Investments, All Other Investments [Abstract] Investments in equity securities of privately-held companies Cost Method Investments, Original Cost GOODWILL AND OTHER INTANGIBLE ASSETS - Net Goodwill and Intangible Assets Disclosure [Text Block] Revenue from Contract with Customer [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASU 2014-09 Accounting Standards Update 2014-09 [Member] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Balances Without Adoption of Topic 606 Calculated under Revenue Guidance in Effect before Topic 606 [Member] Effect of Change Increase (Decrease) Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] 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] Award Type [Domain] Equity Award [Domain] Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [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] Balance, beginning (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Forfeited (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Vested (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Balance, ending (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Balance, weighted-average grant-date fair value per share (in dollars per share)—beginning Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted, weighted-average grant-date fair value per share (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, weighted-average grant-date fair value per share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Vested, weighted-average grant-date fair value per share (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 Balance, weighted-average grant-date fair value per share (in dollars per share)—ending Compensation cost not yet recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Compensation cost not yet recognized period of recognition Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Shares withheld for taxes Shares Paid for Tax Withholding for Share Based Compensation Tax withholding upon vesting of restricted stock awards COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Other Comprehensive Income (Loss), Net of Tax [Abstract] Schedule of Accumulated Other Comprehensive (Loss) Income Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] INVESTMENTS IN PRIVATELY-HELD COMPANIES Cost-method Investments, Description [Text Block] Statement of Financial Position [Abstract] ASSETS Assets [Abstract] CURRENT ASSETS: Assets, Current [Abstract] Cash and cash equivalents Short-term investments Short-term Investments Accounts receivable—Net Accounts Receivable, Net, Current Inventory Inventory, Net Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current LONG-TERM INVESTMENTS Long-term Investments PROPERTY AND EQUIPMENT—NET Deferred contract costs Capitalized Contract Cost, Net DEFERRED TAX ASSETS Deferred Tax Assets, Net of Valuation Allowance, Noncurrent OTHER INTANGIBLE ASSETS—NET Intangible Assets, Net (Excluding Goodwill) GOODWILL Goodwill 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 Accrued payroll and compensation Employee-related Liabilities, Current Income taxes payable Accrued Income Taxes, Current Deferred revenue Deferred Revenue, Current Total current liabilities Liabilities, Current DEFERRED REVENUE Deferred Revenue, Noncurrent INCOME TAX LIABILITIES Accrued Income Taxes, Noncurrent OTHER LIABILITIES Other Liabilities, Noncurrent Total liabilities Liabilities COMMITMENTS AND CONTINGENCIES (Note 9) Commitments and Contingencies STOCKHOLDERS’ EQUITY: Stockholders' Equity Attributable to Parent [Abstract] Common stock, $0.001 par value—300 shares authorized; 168.0 and 167.9 shares issued and outstanding at March 31, 2018 and December 31, 2017, respectively Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock 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 Revenue Recognition Revenue from Contract with Customer [Text Block] Accounting Policies [Abstract] Basis of Presentation and Preparation Presentation and Preparation of Consolidated Financial Statements [Policy Text Block] Presentation and Preparation of Consolidated Financial Statements [Policy Text Block] Recently Adopted Accounting Standards and Recent Accounting Standards Not Yet Effective New Accounting Pronouncements, Policy [Policy Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Exclusive Networks Group [Member] Exclusive Networks Group [Member] Exclusive Networks Group [Member] Fin Tec Computers [Member] Fin Tec Computers [Member] Fin Tec Computers [Member] Concentration Risk by Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Sales Revenue, Net [Member] Sales Revenue, Net [Member] Accounts Receivable [Member] Accounts Receivable [Member] Concentration Risk by Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Customer Concentration Risk [Member] Customer Concentration Risk [Member] Statement, Geographical [Axis] Geographical [Axis] Segment, Geographical [Domain] Geographical [Domain] Americas [Member] Americas [Member] U.S. UNITED STATES CANADA CANADA Other Americas Other Americas [Member] Other Americas [Member] EMEA Europe, Middle East and Africa [Member] Europe, Middle East and Africa [Member] France FRANCE Other EMEA Other Europe, Middle East and African Countries [Member] Other Europe, Middle East and African Countries [Member] APAC Asia Pacific and Japan [Member] Asia Pacific and Japan [Member] All Countries [Domain] All Countries [Domain] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Concentration (percent) Concentration Risk, Percentage Business activity (in business activities) Number of Business Activities Number of business activities Segment managers responsible for operations (in segment managers) Number of Segment Managers Responsible for Operations Number of Segment Managers Responsible for Operations Number of operating segments (in operating segments) Number of Operating Segments Number of reportable segments (in reportable segments) Number of Reportable Segments Revenue Property and equipment - net Retirement Benefits [Abstract] Matching contribution on employee contributions, Percent Defined Contribution Plan, Employer Matching Contribution, Percent of Match Maximum contribution percentage of each employee's eligible earnings, Percent Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Matching contributions to the RRSP and 401(k) Plans Defined Contribution Plan, Employer Matching Contribution, Amount Defined Contribution Plan, Employer Matching Contribution, Amount DEFINED CONTRIBUTION PLANS Compensation and Employee Benefit Plans [Text Block] Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Security Subscription [Member] Security Subscription [Member] Security Subscription [Member] Technical Support [Member] Technical Support [Member] Technical Support [Member] Professional Services and Training [Member] Professional Services and Training [Member] Professional Services and Training [Member] Financial Instruments and Fair Value [Abstract] Financial Instruments and Fair Value [Abstract] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities, Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Corporate debt securities [Member] Corporate Debt Securities [Member] Commercial paper [Member] Commercial Paper, Not Included with Cash and Cash Equivalents [Member] Certificates of deposit and term deposits [Member] Certificates of Deposit [Member] U.S. government and agency securities [Member] US Treasury and Government [Member] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Amortized Cost Available-for-sale Debt Securities, Amortized Cost Basis Unrealized Gains Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax Unrealized Losses Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax Fair Value Available-for-sale Securities, Debt Securities Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] Less Than 12 Months, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Less Than 12 Months, Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 Months or Greater, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value 12 Months or Greater, Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Total, Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss Available-for-sale Securities, Debt Maturities, Fair Value [Abstract] Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract] Due within one year Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value Due within one to three years Available-for-sale Securities, Debt Maturities, after One Year, Fair Value This item represents the fair value of debt securities which are expected to mature after one year from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. Fair Value Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Recurring Basis [Member] Fair Value, Measurements, Recurring [Member] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Fair Value [Member] Estimate of Fair Value Measurement [Member] Reported as [Member] Reported Value Measurement [Member] Money market funds [Member] Money Market Funds, Excluding Commercial Paper [Member] Money Market Funds, Excluding Commercial Paper [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Cash equivalents [Member] Cash Equivalents, Line Item [Member] Cash Equivalents, Line Item [Member] Short-term investments [Member] Short Term Investments, Line Item [Member] Short Term Investments, Line Item [Member] Long-term investments [Member] Long Term Investments, Line Item [Member] Long Term Investments, Line Item [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Level 3 [Member] 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] Available-for-sale securities, Fair Value Disclosure Available-for-sale Securities Total Assets, Fair Value Disclosure Assets, Fair Value Disclosure Inventory Impact of Adopting New Accounting Pronouncement Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Statement of Comprehensive Income [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent [Abstract] Change in unrealized losses on investments Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Tax provision related to change in unrealized losses on investments Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent NET INCOME PER SHARE Earnings Per Share [Text Block] Increase (Decrease) in Deferred Charges Increase (Decrease) in Deferred Charges Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Sales Commissions [Member] Sales Commissions [Member] Sales Commissions [Member] Reserves for sales returns Revenue Recognition, Sales Returns, Reserve for Sales Returns Accounts receivable Deferred revenue recognized in period Contract with Customer, Liability, Revenue Recognized Remaining performance obligation Revenue, Remaining Performance Obligation Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable Customer Refund Liability, Current Customer Refund Liability, Current Revenue recognition period (in years) Revenue Recognition Period Revenue Recognition Period Impairment loss Capitalized Contract Cost, Impairment Loss Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Expected term in years Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Dividend rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Schedule of Earnings Per Share [Table] Schedule of Earnings Per Share [Table] Stock Options [Member] Employee Stock Option [Member] ESPP [Member] Employee Stock [Member] Earnings Per Share [Line Items] Earnings Per Share [Line Items] Earnings Per Share [Line Items] Basic shares: Weighted Average Number of Shares Outstanding, Basic [Abstract] Weighted-average common shares outstanding-basic (in shares) Diluted shares: Effect of potentially dilutive securities: Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract] Employee stock options and purchase rights (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted-average shares used to compute diluted net income per share (in shares) Diluted (in dollars per share) Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of product revenue [Member] Cost of Goods Sold [Member] Cost of Goods Sold [Member] Cost of service revenue [Member] Cost of Services [Member] Cost of Services [Member] Research and development [Member] Research and Development Expense [Member] Sales and marketing [Member] Selling and Marketing Expense [Member] General and administrative [Member] General and Administrative Expense [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] Total stock-based compensation expense Allocated Share-based Compensation Expense Income tax benefit from employee stock option plans Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options New Accounting Pronouncement, Early Adoption [Table] New Accounting Pronouncement, Early Adoption [Table] Deferred Tax Asset [Member] Deferred Tax Asset [Member] Deferred Tax Asset [Member] Other Noncurrent Liabilities [Member] Other Noncurrent Liabilities [Member] Scenario, Forecast [Member] Scenario, Forecast [Member] ASU 2016-02 Accounting Standards Update 2016-02 [Member] New Accounting Pronouncement, Early Adoption [Line Items] New Accounting Pronouncement, Early Adoption [Line Items] Deferred tax assets Retained earnings Deferred tax liability Deferred Tax Liabilities, Deferred Expense Deferred Revenue Deferred Revenue Expected increase to assets and liabilities upon adoption of new accounting pronouncement New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification Weighted-average fair value per share granted (in dollars per share) Shares issued under the ESPP (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Weighted-average price per share issued (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Issued, Weighted Average Price per Share Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Issued, Weighted Average Price per Share Inventory, Current [Table] Inventory, Current [Table] Inventory [Axis] Inventory [Axis] Inventory [Domain] Inventory [Domain] Finished goods inventory held by distributors Finished Goods Inventory Held by Distributor [Member] Finished Goods Inventory Held by Distributor [Member] Inventory [Line Items] Inventory [Line Items] Inventory, Net [Abstract] Raw materials Inventory, Raw Materials, Net of Reserves Finished goods Inventory, Finished Goods, Net of Reserves Inventory Materials at contract manufacturers Inventory, Raw Materials, Net of Reserves, at Contract Manufacturers Inventory, Raw Materials, Net of Reserves, at Contract Manufacturers 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 Excluded from Computation of Earnings Per Share, by Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Stock Compensation Plan [Member] Stock Compensation Plan [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Anti-dilutive securities (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 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] Remaining performance obligation expected to be satisfied (percent) Revenue, Remaining Performance Obligation, Expected Percentage of Obligation Satisfied Revenue, Remaining Performance Obligation, Expected Percentage of Obligation Satisfied Performance obligation expected recognition period for three-fourths of remaining obligation Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Property, Plant and Equipment - Net Property, Plant and Equipment [Table Text Block] SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Significant Accounting Policies [Text Block] Inventory Schedule of Inventory, Current [Table Text Block] Income Tax Disclosure [Abstract] INCOME TAXES Income Tax Disclosure [Text Block] 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] FINANCIAL INSTRUMENTS AND FAIR VALUE Financial Instruments Disclosure [Text Block] STOCKHOLDERS' EQUITY Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Common Stock, par value (dollars per share) Common Stock, Par or Stated Value Per Share Common Stock, shares authorized Common Stock, Shares Authorized Common Stock, shares issued Common Stock, Shares, Issued Common Stock, shares outstanding Common Stock, Shares, Outstanding Operating Lease Commitments: Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Operating lease commitments, 2018 Operating Leases, Future Minimum Payments, Remainder of Fiscal Year Operating lease commitments, 2019 Operating Leases, Future Minimum Payments, Due in Two Years Operating lease commitments, 2020 Operating Leases, Future Minimum Payments, Due in Three Years Operating lease commitments, 2021 Operating Leases, Future Minimum Payments, Due in Four Years Operating lease commitments, 2022 Operating Leases, Future Minimum Payments, Due in Five Years Operating lease commitments, Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Operating lease commitments Operating Leases, Future Minimum Payments Due Inventory purchase commitments: Purchase Obligation, Fiscal Year Maturity [Abstract] Inventory purchase commitments, 2018 Purchase Obligation, Future Minimum Payments, Remainder of Fiscal Year Inventory purchase commitments, 2019 Purchase Obligation, Due in Second Year Inventory purchase commitments, 2020 Purchase Obligation, Due in Third Year Inventory purchase commitments, 2021 Purchase Obligation, Due in Fourth Year Inventory purchase commitments, 2022 Purchase Obligation, Due in Fifth Year Inventory purchase commitments, Thereafter Purchase Obligation, Due after Fifth Year Inventory purchase commitments Purchase Obligation Other contractual commitments and open purchase orders: Other Commitments [Abstract] Contractual Obligation, 2018 Contractual Obligation, Future Minimum Payments Due, Remainder of Fiscal Year Contractual Obligation, 2019 Contractual Obligation, Due in Second Year Contractual Obligation, 2020 Contractual Obligation, Due in Third Year Contractual Obligation, 2021 Contractual Obligation, Due in Fourth Year Contractual Obligation, 2022 Contractual Obligation, Due in Fifth Year Contractual Obligation, Thereafter Contractual Obligation, Due after Fifth Year Contractual Obligation Contractual Obligation Accumulated Other Comprehensive (Loss) Income [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Unrealized Gains and Losses on Investments [Member] Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Accumulated Other Comprehensive (Loss) Income [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive (Loss) Income [Roll Forward] Accumulated Other Comprehensive Income [Roll Forward] Accumulated Other Comprehensive Income [Roll Forward] Beginning balance AOCI Including Portion Attributable to Noncontrolling Interest, before Tax Other comprehensive loss before reclassifications Other Comprehensive Income (Loss), before Reclassifications, before Tax Amounts reclassified from accumulated other comprehensive loss Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Net current-period other comprehensive loss Other Comprehensive Income (Loss), before Tax Ending balance Tax Benefit Related To Items of Other Comprehensive Income or Loss [Roll Forward] Accumulated Other Comprehensive Income, Tax [Roll Forward] Accumulated Other Comprehensive Income, Tax [Roll Forward] Beginning balance, tax Accumulated Other Comprehensive Income Loss Tax Accumulated Other Comprehensive Income Loss Tax Other comprehensive income before reclassifications, tax Other Comprehensive Income (Loss) before Reclassifications, Tax Amounts reclassified from accumulated other comprehensive income, tax Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax Net current-period other comprehensive income, tax Other Comprehensive Income (Loss), Tax Ending balance, tax Effective tax rate (percent) Effective Income Tax Rate Reconciliation, Percent U.S. federal and state taxes, withholding taxes and foreign taxes Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, State and Local Income Taxes, and Foreign Income Tax Rate Differential, , Amount Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, State and Local Income Taxes, and Foreign Income Tax Rate Differential, , Amount Excess tax benefits on stock compensation Effective Income Tax Reconciliation, Excess Tax Benefit on Stock-based Compensation Effective Income Tax Reconciliation, Excess Tax Benefit on Stock-based Compensation Unrecognized tax benefits and related interest release Effective Income Tax Reconciliation, Unrecognized Tax Benefits Effective Income Tax Reconciliation, Unrecognized Tax Benefits Unrecognized tax benefits Unrecognized Tax Benefits Unrecognized tax benefits that would favoraby affect effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Accrued interest and penalties related to uncertain tax benefits Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Possible decrease in unrecognized tax benefits Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Approved refund claim Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] 2016 Share Repurchase Program [Member] Share Repurchase Program [Member] Share Repurchase Program [Member] Share Repurchase Program [Line Items] Stock repurchase program, authorized amount Stock Repurchase Program, Authorized Amount Additional shares authorized Stock Repurchase Program, Additional Authorized Amount Stock Repurchase Program, Additional Authorized Amount Stock repurchased in the period, shares Stock Repurchased and Retired During Period, Shares Stock repurchased, average price (in dollars per share) Treasury Stock Acquired, Average Cost Per Share Stock repurchased in the period, value Stock Repurchased and Retired During Period, Value Stock repurchase program, unused balance Stock Repurchase Program, Remaining Authorized Repurchase Amount Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Fiscal Years: Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] 2018 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2021 and thereafter Finite-Lived Intangible Assets, Amortization Expense, Year Four Total Finite-Lived Intangible Assets, Net Rent expense Operating Leases, Rent Expense, Net Inventory purchase commitments Other contractual commitments and open purchase orders Other Commitment Schedule of Finite-Lived Intangible Assets by Major Class [Table] Schedule of Finite-Lived Intangible Assets [Table] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] In Process Research and Development [Member] In Process Research and Development [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Developed Technologies and Other [Member] Developed Technology Rights [Member] Customer Relationships [Member] Customer Relationships [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Weighted average useful life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Finite-Lived Intangible Assets, Net [Abstract] Finite-Lived Intangible Assets, Net [Abstract] Gross Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract] Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract] In-process research and development Indefinite-Lived Intangible Assets (Excluding Goodwill) Intangible Assets, Net (Excluding Goodwill) [Abstract] Intangible Assets, Net (Excluding Goodwill) [Abstract] Gross Intangible Assets, Gross (Excluding Goodwill) Net Amortization expense Amortization of Intangible Assets Summary of Investments Schedule of Amortized Costs, Unrealized Gains and Losses, and Fair Value of Available For Sale Securities [Table Text Block] Schedule of Amortized Costs, Unrealized Gains and Losses, and Fair Value of Available For Sale Securities [Table Text Block] Schedule of Unrealized Loss on Investments Schedule of Unrealized Loss on Investments [Table Text Block] Investments Classified by Contractual Maturity Date Investments Classified by Contractual Maturity Date [Table Text Block] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] ACCUMULATED OTHER COMPREHENSIVE LOSS Comprehensive Income (Loss) Note [Text Block] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Performance Share, Weighted Average Assumptions [Abstract] Performance Share, Weighted Average Assumptions [Abstract] Performance Share, Weighted Average Assumptions [Abstract] Granted (shares) PROPERTY AND EQUIPMENT—Net Property, Plant and Equipment Disclosure [Text Block] Schedule of Indefinite-Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Indefinite-lived Intangible Assets [Line Items] Indefinite-lived Intangible Assets [Line Items] Goodwill Goodwill impairment Goodwill, Impairment Loss Share Repurchase Program [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Share-based Compensation Arrangement by Share-based Payment Award Authorized Shares Changes [Axis] Share-based Compensation Arrangement by Share-based Payment Award Authorized Shares Changes [Axis] Share-based Compensation Arrangement by Share-based Payment Award Authorized Shares Changes [Axis] Share-based Compensation Arrangement by Share-based Payment Award Authorized Shares Changes [Domain] Share-based Compensation Arrangement by Share-based Payment Award Authorized Shares Changes [Domain] Share-based Compensation Arrangement by Share-based Payment Award Authorized Shares Changes [Domain] Deferred Compensation Arrangement with Individual, Share-based Payments, by Title of Individual [Axis] Title of Individual with Relationship to Entity [Domain] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Stock-based Compensation Plan [Member] Stock repurchase program, remaining repurchase amount Remaining shares available for grant under the plans Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] 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] Balance - Beginning (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Balance - Ending (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Balance - Beginning (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Forfeited (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Balance - Ending (in dollars per share) 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] Options vested and expected to vest, Outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Options vested and expected to vest, Weighted average exercise price (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Options vested and expected to vest, Weighted average remaining contractual life (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Options vested and expected to vest, Aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Options exercisable, Outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Options exercisable, Weighted average exercise price (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Options exercisable, Weighted average remaining contractual life (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Options exercisable, Aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Weighted-average fair value per share granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Total fair value of awards vested Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Revenue from external customers by geographic region Revenue from External Customers by Geographic Areas [Table Text Block] Property and equipment by geographic region Long-lived Assets by Geographic Areas [Table Text Block] Schedule of customer concentration Schedules of Concentration of Risk, by Risk Factor [Table Text Block]