Entity Central Index Key Document and entity information. Document And Entity Information [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key 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 Accrued and other liabilities current. Statement Of Financial Position [Abstract] ASSETS Assets [Abstract] Current assets: Assets Current [Abstract] Cash and cash equivalents Cash And Cash Equivalents At Carrying Value Marketable securities Marketable Securities Accounts receivable, net Accounts Receivable Net Current Inventories Inventory Net Restricted cash Restricted Cash And Cash Equivalents Prepaid expenses and other current assets Prepaid Expense And Other Assets Current Total current assets Assets Current Property and equipment, net Property Plant And Equipment Net Deferred tax assets, non-current Deferred Tax Assets Net Noncurrent Intangible assets, net Intangible Assets Net Excluding Goodwill Goodwill Goodwill Other non-current assets Other Assets Noncurrent Total assets Assets LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities And Stockholders Equity [Abstract] Current liabilities: Liabilities Current [Abstract] Accounts payable Accounts Payable Current Accrued and other current liabilities Accrued And Other Liabilities Current Income taxes payable Accrued Income Taxes Current Deferred revenue Deferred Revenue Current Total current liabilities Liabilities Current Other long-term liabilities Other Liabilities Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 14) Commitments And Contingencies Shareholders' equity: Stockholders Equity [Abstract] Preference shares, $0.00045 par value per share, 20,000,000 shares authorized and no shares issued and outstanding at July 31, 2017 and January 31, 2017, respectively Preferred Stock Value Ordinary shares, $0.00045 par value per share, 200,000,000 shares authorized at July 31, 2017 and January 31, 2017, respectively; 33,220,378 shares issued and outstanding at July 31, 2017; 33,369,032 shares issued and outstanding at January 31, 2017 Common Stock Value Additional paid-in capital Additional Paid In Capital Accumulated other comprehensive loss Accumulated Other Comprehensive Income Loss Net Of Tax Retained earnings Retained Earnings Accumulated Deficit Total shareholders’ equity Stockholders Equity Total liabilities and shareholders' equity Liabilities And Stockholders Equity Preference shares, par value Preferred Stock Par Or Stated Value Per Share Preference shares, shares authorized Preferred Stock Shares Authorized Preference shares, shares issued Preferred Stock Shares Issued Preference shares, shares outstanding Preferred Stock Shares Outstanding Ordinary shares, par value Common Stock Par Or Stated Value Per Share Ordinary shares, shares authorized Common Stock Shares Authorized Ordinary shares, shares issued Common Stock Shares Issued Ordinary shares, shares outstanding Common Stock Shares Outstanding Income Statement [Abstract] Revenue Revenues Cost of revenue Cost Of Revenue Gross profit Gross Profit Operating expenses: Operating Expenses [Abstract] Research and development Research And Development Expense Selling, general and administrative Selling General And Administrative Expense Total operating expenses Operating Expenses Income from operations Operating Income Loss Other income Nonoperating Income Expense Income before income taxes Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest Provision for income taxes Income Tax Expense Benefit Net income Net Income Loss Net income per share attributable to ordinary shareholders: Earnings Per Share [Abstract] Basic Earnings Per Share Basic Diluted Earnings Per Share Diluted Weighted-average shares used to compute net income per share attributable to ordinary shareholders: Weighted Average Number Of Shares Outstanding [Abstract] Basic Weighted Average Number Of Shares Outstanding Basic Diluted Weighted Average Number Of Diluted Shares Outstanding Statement Of Income And Comprehensive Income [Abstract] Net income Other comprehensive income (loss), net of tax: Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract] Unrealized gains (losses) on investments Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax Other comprehensive income (loss), net of tax Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Comprehensive income Comprehensive Income Net Of Tax The increase (decrease) of deferred tax liability attributable to taxable temporary differences. Amount of cash inflow from exercise of stock options and employee stock purchase plan withholding. Amount of cash outflow associated with the payment of software license liabilities. Capital expenditures incurred but not yet paid and financing incurred for intangible and fixed asset purchases. Statement Of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided By Used In Operating Activities Continuing Operations [Abstract] 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] Depreciation of property and equipment Depreciation Depletion And Amortization Amortization of intangible assets Amortization Of Intangible Assets Amortization/accretion of marketable securities Accretion Amortization Of Discounts And Premiums Investments Stock-based compensation Share Based Compensation Other non-cash items, net Other Noncash Income Expense Changes in operating assets and liabilities: Increase Decrease In Operating Capital [Abstract] Accounts receivable Increase Decrease In Accounts Receivable Inventories Increase Decrease In Inventories Prepaid expenses and other current assets Increase Decrease In Prepaid Deferred Expense And Other Assets 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 Income taxes payable Increase Decrease In Accrued Income Taxes Payable Deferred tax liabilities Increase Decrease In Deferred Tax Liabilities Deferred revenue Increase Decrease In Deferred Revenue Other long-term liabilities Increase Decrease In Other Noncurrent Liabilities Net cash provided by operating activities Net Cash Provided By Used In Operating Activities Continuing Operations Cash flows from investing activities: Net Cash Provided By Used In Investing Activities Continuing Operations [Abstract] Purchase of investments Payments To Acquire Available For Sale Securities Sales of investments Proceeds From Sale Of Available For Sale Securities Debt Maturities of investments Proceeds From Sale And Maturity Of Available For Sale Securities 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 Continuing Operations Cash flows from financing activities: Net Cash Provided By Used In Financing Activities Continuing Operations [Abstract] Stock repurchase Payments For Repurchase Of Common Stock Proceeds from exercise of stock options and employee stock purchase plan Proceeds From Issuance Of Shares Under Incentive Equity Plan And Employee Stock Purchase Plan Payment for software license liabilities Payment For Software License Liabilities Net cash used in financing activities Net Cash Provided By Used In Financing Activities Continuing Operations Net increase (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 end of period Supplemental disclosure of cash flow information: Supplemental Cash Flow Information [Abstract] Cash paid for income taxes Income Taxes Paid Supplemental disclosure of noncash investing and financing activities: Noncash Investing And Financing Items [Abstract] Increase in liabilities related to intangible and fixed asset purchases Capital Expenditures Incurred But Not Yet Paid And Financing Incurred For Intangible And Fixed Asset Purchases Accounting Policies [Abstract] Organization and Summary of Significant Accounting Policies Organization Consolidation And Presentation Of Financial Statements Disclosure And Significant Accounting Policies [Text Block] Investments All Other Investments [Abstract] Financial Instruments and Fair Value Financial Instruments Disclosure [Text Block] Inventory Disclosure [Abstract] Inventories Inventory Disclosure [Text Block] Property Plant And Equipment [Abstract] Property and Equipment, Net Property Plant And Equipment Disclosure [Text Block] Goodwill And Intangible Assets Disclosure [Abstract] Intangible Assets Intangible Assets Disclosure [Text Block] Goodwill Goodwill Disclosure [Text Block] Payables And Accruals [Abstract] Accrued and Other Current Liabilities Accounts Payable Accrued Liabilities And Other Liabilities Disclosure Current [Text Block] Deferred Revenue Disclosure [Abstract] Deferred Revenue and Deferred Cost Deferred Revenue Disclosure [Text Block] Other Liabilities Disclosure [Abstract] Other Long-Term Liabilities Accounts Payable Accrued Liabilities And Other Liabilities Disclosure Noncurrent [Text Block] The entire disclosure of an entity's capital stock, shares repurchased, and shares reserved for future issuance. Equity [Abstract] Capital Stock Capital Stock [Text Block] Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] Stock-based Compensation Disclosure Of Compensation Related Costs Share Based Payments [Text Block] Net Income Per Ordinary Share Earnings Per Share [Text Block] Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Commitments And Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments And Contingencies Disclosure [Text Block] Segment Reporting [Abstract] Segment Reporting Segment Reporting Disclosure [Text Block] Related Party Transactions [Abstract] Related-Party Transactions Related Party Transactions Disclosure [Text Block] Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] Formation and business of the entity. Organization Organization Policy [Text Block] Basis of Presentation Basis Of Accounting Policy Policy [Text Block] Basis of Consolidation Consolidation Policy [Text Block] Use of Estimates Use Of Estimates The entire disclosure of concentration risks existing in the entity's business and investment. Concentration of Risk Concentration Of Risk Policy [Text Block] Disclosure of accounting policy for determining cash equivalents and marketable securities. The disclosure may also address accounting policies for investments classified as trading, available for sale, or held to maturity and may include how the entity determines whether impairments of available for sale or held to maturity investments are other than temporary, how the fair values of the entity's securities are determined, and how the entity presents the realized and unrealized gains or losses in its financial statements. Cash Equivalents and Marketable Securities Cash Equivalents And Marketable Securities Policy [Text Block] Inventories Inventory Policy [Text Block] Disclosure of accounting policy for noncancelabe internal-use software license and associated liabilities. Noncancelable Internal-Use Software License Noncancelable Internal Use Software License Policy [Text Block] Business Combinations and Intangible Assets Business Combinations Policy Disclosure of accounting policy for goodwill and in process research and development. Goodwill and In-Process Research and Development Goodwill And In Process Research And Development Policy [Text Block] Revenue Recognition Revenue Recognition Policy [Text Block] Cost of Revenue Cost Of Sales Policy [Text Block] Income Taxes Income Tax Policy [Text Block] Net Income Per Ordinary Share Earnings Per Share Policy [Text Block] Comprehensive Income (Loss) Comprehensive Income Policy Policy [Text Block] Recent Accounting Pronouncements New Accounting Pronouncements Policy Policy [Text Block] Schedule of Available-for-Sale Securities at Fair Value Available For Sale Securities [Text Block] Schedule of Cash Equivalents and Marketable Securities Schedule Of Cash Cash Equivalents And Short Term Investments Table [Text Block] Summary of Contractual Maturities of Investments Investments Classified By Contractual Maturity Date Table [Text Block] Schedule of Fair Value of Financial Instruments Measured on Recurring Basis Fair Value Assets Measured On Recurring Basis [Text Block] Schedule of Inventory Schedule Of Inventory Current Table [Text Block] Schedule of Property and Equipment Property Plant And Equipment [Text Block] Schedule of Accrued and Other Current Liabilities Schedule Of Accounts Payable And Accrued Liabilities Table [Text Block] Schedule of Deferred Revenue and Related Cost Deferred Revenue By Arrangement Disclosure [Text Block] Schedule of Other Long-Term Liabilities Other Noncurrent Liabilities Table [Text Block] Summary of ordinary shares reserved for future issuance. Schedule of Ordinary Shares Reserved for Future Issuance under EIP and ESPP Summary Of Ordinary Shares Reserved For Future Issuance Table [Text Block] Classification of Stock-based Compensation Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Text Block] Weighted-Average Assumptions Used to Estimate Fair Value 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 and Restricted Stock Units Activities Schedule Of Sharebased Compensation Restricted Stock And Restricted Stock Units Activity Table [Text Block] Computation of Basic and Diluted Net Income Per Ordinary Share Schedule Of Earnings Per Share Basic And Diluted Table [Text Block] Weighted-Average Potentially Dilutive Securities Excluded from Computation of Diluted Net Income Per Ordinary Share Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Text Block] Schedule of income tax expense and effective tax rate. Summary of Income Taxes Schedule Of Income Tax Expenses And Effective Tax Rate Table [Text Block] Future Annual Minimum Lease Payments Schedule Of Future Minimum Rental Payments For Operating Leases Table [Text Block] Company's Revenue by Geographic Region Based on Bill-to Location Schedule Of Revenue From External Customers Attributed To Foreign Countries By Geographic Area [Text Block] Investments Debt And Equity Securities [Abstract] Schedule Of Available For Sale Securities [Table] Schedule Of Available For Sale Securities [Table] Investment Type Investment Type [Axis] Investments Investment Type Categorization [Member] Money market funds [Member] Money Market Funds [Member] Demand deposits [Member] Demand Deposits [Member] Commercial paper [Member] Commercial Paper [Member] Corporate bonds [Member] Bonds [Member] Asset-backed securities [Member] Asset Backed Securities [Member] U.S. government securities [Member] U S Treasury Securities [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 Investments by Category Gain Loss On Investments By Category [Axis] Marketable Securities and Investments Held at Cost Gain Loss On Investments Including Marketable Securities And Investments Held At Cost Categories Of Investments [Domain] Included in marketable securities [Member] Availableforsale Securities [Member] Asset Class Fair Value By Asset Class [Axis] Asset Class Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation By Asset Class [Domain] Included in cash equivalents [Member] Cash Equivalents [Member] Total cash equivalents and marketable securities Fair value of available-for-sale debt securities maturing within one to two years following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Available For Sale Securities Debt Maturities Fair Value [Abstract] Due within one year Available For Sale Securities Debt Maturities Next Rolling Twelve Months Fair Value Due within one to two years Available For Sale Securities Debt Maturities Within One To Two Years Fair Value Total cash equivalents and marketable securities Fair Value Disclosures [Abstract] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Level 2 [Member] Fair Value By Fair Value Hierarchy Level [Axis] Fair Value Hierarchy Fair Value Measurements Fair Value Hierarchy [Domain] Level 1 [Member] Fair Value Inputs Level1 [Member] Level 2 [Member] Fair Value Inputs Level2 [Member] Level 3 [Member] Fair Value Inputs Level3 [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] Work-in-progress Inventory Work In Process Net Of Reserves Finished goods Inventory Finished Goods Net Of Reserves Total Schedule Of Property Plant And Equipment [Table] Schedule Of Property Plant And Equipment [Table] Property, Plant and Equipment, Type Property Plant And Equipment By Type [Axis] Property, Plant and Equipment, Type Property Plant And Equipment Type [Domain] Computer equipment and software [Member] Computer Equipment [Member] Machinery and equipment [Member] Machinery And Equipment [Member] Furniture and fixtures [Member] Furniture And Fixtures [Member] Leasehold improvements [Member] Leasehold Improvements [Member] Construction in progress [Member] Construction In Progress [Member] Property Plant And Equipment [Line Items] Property Plant And Equipment [Line Items] Property and equipment, gross Property Plant And Equipment Gross Less: accumulated depreciation and amortization Accumulated Depreciation Depletion And Amortization Property Plant And Equipment Total property and equipment, net Schedule Of Finite Lived Intangible Assets [Table] Schedule Of Finite Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class Finite Lived Intangible Assets By Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name Finite Lived Intangible Assets Major Class Name [Domain] IPR&D [Member] In Process Research And Development [Member] Non cancelable software licenses. Noncancelable software license [Member] Non Cancelable Software Licenses [Member] Business Acquisition Business Acquisition [Axis] Business Acquisition, Acquiree Business Acquisition Acquiree [Domain] VisLab S.r.l. Vis Lab SRL [Member] Vis Lab S R L [Member] Balance Sheet Location Balance Sheet Location [Axis] Balance Sheet Location Balance Sheet Location [Domain] Accrued and other current liabilities. Accrued and other current liabilities [Member] Accrued And Other Current Liabilities [Member] Other long term liabilities. Other long-term liabilities [Member] Other Long Term Liabilities [Member] Finite Lived Intangible Assets [Line Items] Finite Lived Intangible Assets [Line Items] Intangible assets acquired Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Other Than Goodwill Amortization of intangible asset Finite Lived Intangible Assets Accumulated Amortization Commitment noncancelable software license payment. Noncancelable internal-use software license amortization expense. Current portion of liabilities associated with noncancelable internal-use software license recorded at net present value. Non-current portion of liabilities associated with noncancelable internal-use software license recorded at net present value. Committed to make license payment through January 2020 Commitment Noncancelable Software License Payment Liabilities associated with noncancelable internal-use software license at net present value, current Liabilities Associated With Noncancelable Internal Use Software License At Net Present Value Current Liabilities associated with noncancelable internal-use software license at net present value, non-current Liabilities Associated With Noncancelable Internal Use Software License At Net Present Value Noncurrent Noncancelable software license, amortization expense Noncancelable Internal Use Software License Amortization Impairment of intangible assets Impairment Of Intangible Assets Excluding Goodwill Business acquisition date Business Acquisition Effective Date Of Acquisition1 Cash paid for business acquisition Payments To Acquire Businesses Gross Intangible assets acquired Net assets acquired Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net Deferred tax liabilities, intangible assets Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets Goodwill impairment Goodwill Impairment Loss Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated rebates granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated research and development cost. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Current portion of liabilities associated with noncancelable internal-use software license. Accrued employee compensation Employee Related Liabilities Current Accrued warranty Product Warranty Accrual Classified Current Accrued rebates Accrued Rebates Accrued product development costs Accrued Development Cost Liabilities Software license liabilities, current Software License Liabilities Current Other accrued liabilities Other Accrued Liabilities Current Total accrued and other current liabilities Deferred revenue from product shipments. Deferred revenue from services. Deferred cost associated with deferred revenue from product shipments. Deferred revenue from product shipments Deferred Revenue From Product Shipments Deferred revenue from services Deferred Revenue From Services Deferred cost of revenue from product shipments Deferred Cost Of Revenue From Product Shipments Total deferred revenue, net Unrecognized tax benefits, including interest, recorded in the balance sheet. Non-current portion of liabilities associated with noncancelable internal-use software license. Unrecognized tax benefits, including interest Unrecognized Tax Benefits Including Interest Deferred tax liabilities, non-current Deferred Tax Liabilities Gross Noncurrent Software license liabilities, non-current Software License Liabilities Non Current Other long-term liabilities Other Sundry Liabilities Noncurrent Total other long-term liabilities Schedule Of Stock By Class [Table] Schedule Of Stock By Class [Table] Plan Name Plan Name [Axis] Plan Name Plan Name [Domain] 2012 Equity Incentive Plan. 2012 Equity Incentive Plan [Member] Two Thousand Twelve Equity Incentive Plan [Member] Scenario Statement Scenario [Axis] Scenario, Unspecified Scenario Unspecified [Domain] Scenario, plan automatically increased by the lessor of [Member] Scenario Plan [Member] Amended and restated 2012 employee stock purchase plan. Amended and Restated 2012 Employee Stock Purchase Plan [Member] Amended And Restated Two Thousand Twelve Employee Stock Purchase Plan [Member] Range Range [Axis] Range Range [Member] Maximum [Member] Maximum [Member] Stock repurchase program authorization. Stock Repurchase Program $75.0 Million Authorization [Member] Stock Repurchase Program Authorization [Member] Stock repurchase program additional authorization. Stock Repurchase Program $50.0 Million Authorization [Member] Stock Repurchase Program Additional Authorization [Member] Class Of Stock [Line Items] Class Of Stock [Line Items] Annual increase in ordinary shares for available for future issuance. Annual increase in shares for available for future issuance by percentage of outstanding ordinary shares as of last day of immediately preceding fiscal year. Additional ordinary shares reserved for issuance Share Based Compensation Arrangement By Share Based Payment Award Number Of Additional Shares Authorized Annual increase in ordinary shares for available for future issuance Annual Increase In Ordinary Shares For Available For Future Issuance Annual shares increase for future issuance by percentage under 2012 equity incentive plan Annual Increase In Shares For Available For Future Issuance By Percentage Of Outstanding Ordinary Shares As Of Last Day Of Immediately Preceding Fiscal Year Number of additional shares authorized for issuance under an established purchase plan. Annual increase in shares for available for future issuance by percentage of the outstanding ordinary shares on the first day of such fiscal year. Additional ordinary shares reserved for issuance Additional Common Stock Capital Shares Reserved For Future Issuance Annual shares increase for future issuance by percentage under 2012 employee stock purchase plan Annual Increase In Shares For Available For Future Issuance By Percentage Of Outstanding Ordinary Shares On First Day Of Such Fiscal Year Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Equity Incentive Plan. EIP [Member] Equity Incentive Plan [Member] Employee Stock Purchase Plan. ESPP [Member] Employee Stock Purchase Plan [Member] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Shares reserved Common Stock Capital Shares Reserved For Future Issuance Stock repurchase program authorization date. Stock repurchase program commencement date. Amount authorized under stock repurchase program Stock Repurchase Program Authorized Amount1 Stock repurchase program, authorization date Stock Repurchase Program Authorization Date Stock repurchase program, expiration date Stock Repurchase Program Expiration Date Stock repurchase program, period Stock Repurchase Program Period In Force1 Stock repurchase program, commencing date Stock Repurchase Program Commencement Date Stock repurchased during period, shares Stock Repurchased During Period Shares Stock repurchased during period, cash Amount available under stock repurchase program Stock Repurchase Program Remaining Authorized Repurchase Amount1 Stock based compensation. 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 Income Statement Location [Axis] Income Statement Location Income Statement Location [Domain] Cost of revenue [Member] Cost Of Sales [Member] Research and development [Member] Research And Development Expense [Member] Selling, general and administrative [Member] Selling General And Administrative Expenses [Member] Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] Stock-based compensation: Stock Based Compensation [Abstract] Total stock-based compensation Allocated Share Based Compensation Expense Award Type Award Type [Axis] Equity Award Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain] Stock options [Member] Employee Stock Option [Member] Restricted stock units [Member] Restricted Stock Units R S U [Member] Restricted Stock Awards [Member] Restricted Stock [Member] Restricted stock and restricted stock units. Restricted Stock and Restricted Stock Units [Member] Restricted Stock And Restricted Stock Units [Member] Total unrecognized compensation cost, stock options Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options Total unrecognized compensation cost, restricted stock units Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options Weighted average recognition period Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 Total unrecognized compensation cost, restricted stock awards Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Employee stock purchase plan awards [Member] 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 Expected term (years) Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 Dividend yield Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate Shares, Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Shares, Granted Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross Shares, Exercised Stock Issued During Period Shares Stock Options Exercised Shares, Forfeited Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period Shares, Expired Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period Shares, Outstanding Shares, Exercisable Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Weighted-Average Exercise Price, Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price Weighted-Average Exercise Price, Granted Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price Weighted-Average Exercise Price, Exercised Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price Weighted-Average Exercise Price, Forfeited Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price Weighted-Average Exercise Price, Expired Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price Weighted-Average Exercise Price, Outstanding Weighted-Average Exercise Price, Exercisable Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price Weighted-Average Grant-date Fair Value, Granted Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value Total Intrinsic Value Of Options Exercised Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value Weighted-Average Remaining Contractual Term, Outstanding Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 Weighted-Average Remaining Contractual Term, Exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 Aggregate Intrinsic Value, Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value Aggregate Intrinsic Value, Exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 Closing market price of ordinary shares on NASDAQ on the last day of reporting period. Closing price of ordinary shares Closing Market Price Of Ordinary Shares On N A S D A Q On Last Day Of Reporting Period Restricted stock and restricted stock units [Member] Shares, Unvested, beginning balance Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Shares, Granted Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Shares, Vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Shares, Forfeited Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period Shares, Unvested, ending balance Weighted-Average Grant-Date Fair Value, Unvested, beginning balance Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value Weighted-Average Grant-Date Fair Value, Granted Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value Weighted-Average Grant-Date Fair Value, Vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value Weighted-Average Grant-Date Fair Value, Forfeited Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value Weighted-Average Grant-Date Fair Value, Unvested, ending balance Aggregate intrinsic value of unvested restricted stock and restricted stock units Sharebased Compensation Arrangement By Sharebased Payment Award Equity Instruments Other Than Options Aggregate Intrinsic Value Nonvested Numerator: Net Income Loss [Abstract] Denominator: Weighted-average ordinary shares - basic Effect of potentially dilutive securities: Dilutive Securities [Abstract] Employee stock options Incremental Common Shares Attributable To Share Based Payment Arrangements Restricted stock and restricted stock units Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends Employee stock purchase plan Incremental Common Shares Attributable To Equity Unit Purchase Agreements Weighted-average ordinary shares - diluted Net income per ordinary share: Earnings Per Share Basic And Diluted [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 Antidilutive Securities Excluded From Computation Of Earnings Per Share By Antidilutive Securities [Axis] Antidilutive Securities, Name Antidilutive Securities Name [Domain] Options to purchase ordinary 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 shares excluded from computation of earnings per share Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount Income before income taxes Effective tax rate Effective Income Tax Rate Continuing Operations Tax year that remains open to examination under enacted tax laws, in CCYY format. Income taxes. Income taxes. Income Taxes [Table] Income Taxes [Table] Income Tax Authority Income Tax Authority [Axis] Income Tax Authority Income Tax Authority [Domain] U.S. federal tax authorities [Member] Domestic Country [Member] U.S. state tax authorities [Member] State And Local Jurisdiction [Member] Foreign tax authorities [Member] Foreign Country [Member] Tax Period Tax Period [Axis] Tax Period Tax Period [Domain] Earliest tax year [Member] Earliest Tax Year [Member] Latest tax year [Member] Latest Tax Year [Member] Income Taxes [Line Items] Income Taxes [Line Items] Income tax examination, year Tax Years Subject To Examination Unrecognized tax benefits Unrecognized Tax Benefits Loss Contingencies [Table] Loss Contingencies [Table] Loss Contingency Nature Loss Contingencies By Nature Of Contingency [Axis] Loss Contingency, Nature Loss Contingency Nature [Domain] Indemnification agreement [Member] Indemnification Guarantee [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Net operating lease expense Operating Leases Rent Expense Net 2018 Operating Leases Future Minimum Payments Due Current 2019 Operating Leases Future Minimum Payments Due In Two Years 2020 Operating Leases Future Minimum Payments Due In Three Years 2021 Operating Leases Future Minimum Payments Due In Four Years 2022 Operating Leases Future Minimum Payments Due In Five Years Total future annual minimum lease payments Operating Leases Future Minimum Payments Due Total manufacturing purchase commitments Purchase Commitment Remaining Minimum Amount Committed Payments under indemnification obligations Loss Contingency Damages Paid Value Liabilities recorded under indemnification obligations Loss Contingency Accrual At Carrying Value Concentration Risk [Table] Concentration Risk [Table] Geographical Statement Geographical [Axis] Geographical Segment Geographical [Domain] United States [Member] UNITED STATES Asia Pacific [Member] Asia Pacific [Member] Concentration Risk Benchmark Concentration Risk By Benchmark [Axis] Concentration Risk Benchmark Concentration Risk Benchmark [Domain] Sales revenue, net [Member] Sales Revenue Net [Member] Accounts receivable [Member] Accounts Receivable [Member] Customer Major Customers [Axis] Customer Name Of Major Customer [Domain] Wintech Microelectronics Company, Limited. Wintech [Member] Wintech Microelectronics Company Limited [Member] Chicony Electronics Company Limited. Chicony [Member] Chicony Electronics Company Limited [Member] Concentration Risk Type Concentration Risk By Type [Axis] Concentration Risk Type Concentration Risk Type [Domain] Customer concentration risk [Member] Customer Concentration Risk [Member] Credit concentration risk [Member] Credit Concentration Risk [Member] Minimum [Member] Minimum [Member] Concentration Risk [Line Items] Concentration Risk [Line Items] Number of reportable segment Number Of Reportable Segments Schedule Of Entity Wide Information Revenue From External Customers By Products And Services [Table] Schedule Of Entity Wide Information Revenue From External Customers By Products And Services [Table] Taiwan [Member] TAIWAN, PROVINCE OF CHINA Europe [Member] Europe [Member] North America other than united states. North America other than United States [Member] North America Other Than United States [Member] Revenue from External Customer [Line Items] Entity Wide Information Revenue From External Customer [Line Items] Total revenue Property and equipment, net Major customer revenue percentage. Percentage of revenue or accounts receivable Concentration Risk Percentage1 Percentage of revenue Major Customer Revenue Percentage Accounts receivable Minimum ownership percentage of voting stock used to define related party at the end of reporting period. Schedule Of Related Party Transactions By Related Party [Table] Schedule Of Related Party Transactions By Related Party [Table] Related Party Related Party Transactions By Related Party [Axis] Related Party Related Party [Domain] An officer or employee of another entity serves on the company's board of directors. Other Entity [Member] Other Entity [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Percentage of entity's voting stock owned by related party Minimum Percentage Of Voting Stock Used To Define Related Party Amount paid to related party. Software license expense rent from related party. Payment for license fees Related Party Transaction Amounts Paid To Related Party License expenses included in research and development expense Software License Expense Rent From Related Party Subsequent Event [Table] Subsequent Event [Table] Subsequent Event Type Subsequent Event Type [Axis] Subsequent Event Type Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items]