75000 - Document - Cover Page link:presentationLink link:calculationLink link:definitionLink 75010 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS link:presentationLink link:calculationLink link:definitionLink 75020 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 75030 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS link:presentationLink link:calculationLink link:definitionLink 75040 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME link:presentationLink link:calculationLink link:definitionLink 75050 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 75060 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY link:presentationLink link:calculationLink link:definitionLink 75070 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 75080 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS link:presentationLink link:calculationLink link:definitionLink 995457 - Disclosure - The Company link:presentationLink link:calculationLink link:definitionLink 995467 - Disclosure - Accounting Policies link:presentationLink link:calculationLink link:definitionLink 995477 - Disclosure - Recently Issued Accounting Pronouncements link:presentationLink link:calculationLink link:definitionLink 995487 - Disclosure - Acquisitions link:presentationLink link:calculationLink link:definitionLink 995497 - Disclosure - Revenue link:presentationLink link:calculationLink link:definitionLink 995507 - Disclosure - Equity Method Investments link:presentationLink link:calculationLink link:definitionLink 995517 - Disclosure - Dispositions link:presentationLink link:calculationLink link:definitionLink 995527 - Disclosure - Inventories link:presentationLink link:calculationLink link:definitionLink 995537 - Disclosure - Financial Instruments link:presentationLink link:calculationLink link:definitionLink 995547 - Disclosure - Debt link:presentationLink link:calculationLink link:definitionLink 995557 - Disclosure - Prepayments link:presentationLink link:calculationLink link:definitionLink 995567 - Disclosure - Product Warranty link:presentationLink link:calculationLink link:definitionLink 995577 - Disclosure - Stock-Based Compensation link:presentationLink link:calculationLink link:definitionLink 995587 - Disclosure - Accumulated Other Comprehensive Income (Loss) link:presentationLink link:calculationLink link:definitionLink 995597 - Disclosure - Goodwill and Acquired Intangible Assets link:presentationLink link:calculationLink link:definitionLink 995607 - Disclosure - Earnings Per Common Share Attributable to Teradyne link:presentationLink link:calculationLink link:definitionLink 995617 - Disclosure - Restructuring and Other link:presentationLink link:calculationLink link:definitionLink 995627 - Disclosure - Retirement Plans link:presentationLink link:calculationLink link:definitionLink 995637 - Disclosure - Commitments and Contingencies link:presentationLink link:calculationLink link:definitionLink 995647 - Disclosure - Income Taxes link:presentationLink link:calculationLink link:definitionLink 995657 - Disclosure - Segment Information link:presentationLink link:calculationLink link:definitionLink 995667 - Disclosure - Equity link:presentationLink link:calculationLink link:definitionLink 995677 - Disclosure - Subsequent Events link:presentationLink link:calculationLink link:definitionLink 995687 - Disclosure - Accounting Policies (Policies) link:presentationLink link:calculationLink link:definitionLink 995697 - Disclosure - Acquisitions (Tables) link:presentationLink link:calculationLink link:definitionLink 995707 - Disclosure - Revenue (Tables) link:presentationLink link:calculationLink link:definitionLink 995717 - Disclosure - Equity Method Investments (Tables) link:presentationLink link:calculationLink link:definitionLink 995727 - Disclosure - Dispositions (Tables) link:presentationLink link:calculationLink link:definitionLink 995737 - Disclosure - Inventories (Tables) link:presentationLink link:calculationLink link:definitionLink 995747 - Disclosure - Financial Instruments (Tables) link:presentationLink link:calculationLink link:definitionLink 995757 - Disclosure - Debt (Tables) link:presentationLink link:calculationLink link:definitionLink 995767 - Disclosure - Prepayments (Tables) link:presentationLink link:calculationLink link:definitionLink 995777 - Disclosure - Product Warranty (Tables) link:presentationLink link:calculationLink link:definitionLink 995787 - Disclosure - Stock-Based Compensation (Tables) link:presentationLink link:calculationLink link:definitionLink 995797 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables) link:presentationLink link:calculationLink link:definitionLink 995807 - Disclosure - Goodwill and Acquired Intangible Assets (Tables) link:presentationLink link:calculationLink link:definitionLink 995817 - Disclosure - Earnings Per Common Share Attributable to Teradyne (Tables) link:presentationLink link:calculationLink link:definitionLink 995827 - Disclosure - Retirement Plans (Tables) link:presentationLink link:calculationLink link:definitionLink 995837 - Disclosure - Income Taxes (Tables) link:presentationLink link:calculationLink link:definitionLink 995847 - Disclosure - Segment Information (Tables) link:presentationLink link:calculationLink link:definitionLink 995857 - Disclosure - Accounting Policies - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995867 - Disclosure - Acquisitions - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995877 - Disclosure - Acquisitions - Summary of Final Allocation of Purchase Price (Detail) link:presentationLink link:calculationLink link:definitionLink 995887 - Disclosure - Acquisitions - Summary of Components of Intangible Assets and their Estimated Useful Lives at Acquisition Date (Detail) link:presentationLink link:calculationLink link:definitionLink 995897 - Disclosure - Revenue - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995907 - Disclosure - Disaggregated Revenue by Primary Geographical Market, Major Product Line and Timing of Revenue Recognition (Detail) link:presentationLink link:calculationLink link:definitionLink 995917 - Disclosure - Disaggregated Revenue by Primary Geographical Market, Major Product Line and Timing of Revenue Recognition (Parenthetical) (Detail) link:presentationLink link:calculationLink link:definitionLink 995927 - Disclosure - Deferred Revenue and Customer Advances (Detail) link:presentationLink link:calculationLink link:definitionLink 995937 - Disclosure - Schedule of Assets and Liabilities Related to the DIS Sale Agreement (Detail) link:presentationLink link:calculationLink link:definitionLink 995947 - Disclosure - Equity Method Investments - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995957 - Disclosure - Equity Method Investments - Summary of Change in Carrying Value of Equity Method Investment (Detail) link:presentationLink link:calculationLink link:definitionLink 995967 - Disclosure - Dispositions - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995977 - Disclosure - Composition of Inventories, Net (Detail) link:presentationLink link:calculationLink link:definitionLink 995987 - Disclosure - Composition of Inventories, Net (Parenthetical) (Detail) link:presentationLink link:calculationLink link:definitionLink 995997 - Disclosure - Inventories - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996007 - Disclosure - Realized and Unrealized Gains and Loss (Detail) link:presentationLink link:calculationLink link:definitionLink 996017 - Disclosure - Financial Instruments - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996027 - Disclosure - Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) link:presentationLink link:calculationLink link:definitionLink 996037 - Disclosure - Schedule of Reported Financial Assets and Liabilities (Detail) link:presentationLink link:calculationLink link:definitionLink 996047 - Disclosure - Schedule of Reported Financial Assets and Liabilities (Parenthetical) (Details) link:presentationLink link:calculationLink link:definitionLink 996057 - Disclosure - Schedule of Carrying Amounts and Fair Values of Financial Instruments (Detail) link:presentationLink link:calculationLink link:definitionLink 996067 - Disclosure - Schedule of Available for Sale Marketable Securities (Detail) link:presentationLink link:calculationLink link:definitionLink 996077 - Disclosure - Schedule of Reported Available for Sale Marketable Securities (Detail) link:presentationLink link:calculationLink link:definitionLink 996087 - Disclosure - Contractual Maturities of Investments in Debt Securities Held (Detail) link:presentationLink link:calculationLink link:definitionLink 996097 - Disclosure - Schedule of Notional Amount of Derivatives (Detail) link:presentationLink link:calculationLink link:definitionLink 996107 - Disclosure - Schedule of Derivative Instruments in Statement of Financial Position at Fair Value (Detail) link:presentationLink link:calculationLink link:definitionLink 996117 - Disclosure - Schedule of Effect of Derivative Instruments in Statement of Operations Recognized (Detail) link:presentationLink link:calculationLink link:definitionLink 996127 - Disclosure - Schedule of Effect of Derivative Instruments in Statement of Operations Recognized (Parenthetical) (Details) link:presentationLink link:calculationLink link:definitionLink 996137 - Disclosure - Debt - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996147 - Disclosure - Interest Expense on Teradyne's Senior Notes (Detail) link:presentationLink link:calculationLink link:definitionLink 996157 - Disclosure - Schedule of Prepayments and Other Current Assets (Detail) link:presentationLink link:calculationLink link:definitionLink 996167 - Disclosure - Prepayments - Schedule of Prepayments and Other Current Assets (Parenthetical) (Details) link:presentationLink link:calculationLink link:definitionLink 996177 - Disclosure - Warranty Accrual Included in Other Accrued Liabilities (Detail) link:presentationLink link:calculationLink link:definitionLink 996187 - Disclosure - Extended Product Warranty of Short and Long-Term Deferred Revenue and Customer Advances (Detail) link:presentationLink link:calculationLink link:definitionLink 996197 - Disclosure - Stock-Based Compensation - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996207 - Disclosure - Schedule of Estimated Fair Value of TSR Performance-Based Restricted Stock Unit Awards Assumptions (Detail) link:presentationLink link:calculationLink link:definitionLink 996217 - Disclosure - Schedule of Estimated Fair Value of Stock Options Grant Using Black Scholes Option Pricing Model (Detail) link:presentationLink link:calculationLink link:definitionLink 996227 - Disclosure - Changes in Accumulated Other Comprehensive Income (loss) (Detail) link:presentationLink link:calculationLink link:definitionLink 996237 - Disclosure - Changes in Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) link:presentationLink link:calculationLink link:definitionLink 996247 - Disclosure - Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statement of Operations (Detail) link:presentationLink link:calculationLink link:definitionLink 996257 - Disclosure - Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statement of Operations (Parenthetical) (Detail) link:presentationLink link:calculationLink link:definitionLink 996267 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Additional Information (Details) link:presentationLink link:calculationLink link:definitionLink 996277 - Disclosure - Goodwill and Acquired Intangible Assets - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996287 - Disclosure - Changes in Carrying Amount of Goodwill by Segment (Detail) link:presentationLink link:calculationLink link:definitionLink 996297 - Disclosure - Schedule of Amortizable Intangible Assets (Detail) link:presentationLink link:calculationLink link:definitionLink 996307 - Disclosure - Schedule of Amortizable Intangible Assets (Parenthetical) (Detail) link:presentationLink link:calculationLink link:definitionLink 996317 - Disclosure - Schedule of Estimated Intangible Asset Amortization Expense (Detail) link:presentationLink link:calculationLink link:definitionLink 996327 - Disclosure - Earnings Per Common Share Attributable to Teradyne - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996337 - Disclosure - Computation of Basic and Diluted Earnings Per Common Share Attributable to Teradyne (Detail) link:presentationLink link:calculationLink link:definitionLink 996347 - Disclosure - Restructuring and Other - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996357 - Disclosure - Retirement Plans - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996367 - Disclosure - Schedule of Net Periodic Pension and Postretirement Cost (Detail) link:presentationLink link:calculationLink link:definitionLink 996377 - Disclosure - Commitments and Contingencies - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996387 - Disclosure - Income Taxes - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996397 - Disclosure - Schedule of Reconciliation of Effective Tax Rate (Detail) link:presentationLink link:calculationLink link:definitionLink 996407 - Disclosure - Segment Information - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996417 - Disclosure - Schedule of Segment Information (Detail) link:presentationLink link:calculationLink link:definitionLink 996427 - Disclosure - Schedule of Segment Reporting Information by Segment Charges (Detail) link:presentationLink link:calculationLink link:definitionLink 996437 - Disclosure - Equity - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink Equity Securities, FV-NI, Total Equity Securities, FV-NI Available for sale equity securities Retirement Plan Type [Axis] Retirement Plan Type [Axis] Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Unrealized (losses) gains arising during period, net of tax of $0, $(51), $0, and $(109), respectively Segments [Domain] Segments [Domain] U.S. Qualified Pension Plan US Qualified Pension Plan [Member] US Qualified Pension Plan. Entity Incorporation, State or Country Code Statement of Financial Position Location, Balance [Domain] Balance Sheet Location [Domain] Disposal Group, Including Discontinued Operation, Inventory, Current Inventories, net Defined Benefit Plan, Plan Assets, Contributions by Employer Contribution to defined benefit pension plans Prepaid expense disclosure. Prepaid Expense Disclosure [Text Block] Prepayments Revision of Prior Period [Axis] Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Due within one year, fair market value Treasury Stock Acquired, Average Cost Per Share Common stock average price Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants Convertible note hedge warrant shares Equity [Abstract] Entity Current Reporting Status Option two. Option Two [Member] Conversion option two Loss Contingency, Damages Sought, Value Legal claims, damage sought by party Reduction in pension benefit obligation and pension assets Defined benefit plan, benefit obligation and pension assets, period increase (decrease) Defined Benefit Plan, Benefit Obligation and Pension Assets, Period Increase (Decrease) Dividends Payable, Amount Per Share Goodwill, Gross Goodwill Operating Expenses [Abstract] Operating expenses: Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Commitments and Contingencies Disclosure [Text Block] Commitments and Contingencies Common Stock, Shares Authorized Common stock, shares authorized Service Based Restricted Stock Units [Member] Service Based Restricted Stock Units [Member] Service-Based Restricted Stock Units Finite-Lived Intangible Assets, Amortization Expense, Year Four 2029 Other Nonoperating Income (Expense) [Member] Other (income) expense, net Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax Unrealized gains (losses) on marketable securities arising during period, net of tax Product and Service [Axis] Product and Service [Axis] Document Fiscal Period Focus Revenue from Contract with Customer [Abstract] Entity Shell Company Other Accrued Liabilities, Current Other accrued liabilities Service [Member] Service [Member] Cash and Cash Equivalents, at Carrying Value, Total Cash and Cash Equivalent Cash and cash equivalents Extended Product Warranty Accrual, Total Extended Product Warranty Accrual Balance at end of period Balance at beginning of period Extended warranty Common Stock, Shares, Issued Common stock, shares issued Foreign Plan [Member] Foreign Pension Plans, Defined Benefit Statement [Table] Statement [Table] Other Accrued Liabilities, Noncurrent Long-term other accrued liabilities Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted average grant date fair value of restricted stock units granted Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Percentage of common stock price paid Americas [Member] Americas Statement [Line Items] Statement [Line Items] Business Combination [Domain] Business Acquisition, Acquiree [Domain] Effect of Change in Accounting Estimate, Type [Axis] Warrant [Member] Entity Filer Category Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement Settlement loss (gain) Settlement loss (gain) Non-cash settlement gain Quantifi [Member] Quantifi. Quantifi Schedule of foreign currency cash flow hedges. Schedule of Foreign Currency Cash Flow Hedges [Table Text Block] Schedule of Foreign Currency Cash Flow Hedges Liabilities and Equity Total liabilities and equity Debt Instrument [Line Items] Debt Instrument Amortization, Total Amortization Amortization Restructuring Type [Axis] Restructuring Type Severance Costs Severance benefit and charges Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Option One [Member] Option One [Member] Conversion option one Prepayments [Abstract] Prepayments Abstract Cash and Cash Equivalents, Fair Value Disclosure Cash and cash equivalents Teradyne. Teradyne [Member] Standard and Extended Product Warranty Accrual, Decrease for Payments Settlements made during the period Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent U.S. statutory federal tax rate Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease), Total Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease) Reduction in pension benefit obligation Share Repurchase Program [Table] Derivative Asset, Notional Amount Derivative Asset, Notional amounts Goodwill, Ending Balance Goodwill, Beginning Balance Goodwill Goodwill Total Goodwill Other Noncash Income (Expense), Total Other Noncash Income (Expense) Other Effective Income Tax Rate Reconciliation, Percent Effective tax rate Effective tax rate Employee Stock Option [Member] Investment Income, Interest Interest income Income Tax Jurisdiction [Axis] Income Tax Authority [Axis] Geographical [Domain] Geographical [Domain] Payments for (Proceeds from) Life Insurance Policies, Total Payments for (Proceeds from) Life Insurance Policies Proceeds from insurance Increase (Decrease) in Accounts Payable and Other Operating Liabilities Accounts payable and other liabilities Schedule Of Net Income (Loss) Per Common Share [Table] Schedule Of Net Income Loss Per Common Share [Table] Schedule Of Net Income Loss Per Common Share Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost Due after 10 years, cost Property additions Segment, Expenditure, Addition to Long-Lived Assets Schedule of Inventory, Current [Table Text Block] Composition of Inventories, Net Additional Paid in Capital, Common Stock Additional paid-in capital Foreign currency translation adjustments. Foreign Currency Translation Adjustments [Member] Foreign Currency Translation Reclassification Adjustments Engineering And Development Expense Engineering and development expense. Engineering and development Available for sale securities gross realized loss. Available for Sale Securities Gross Realized Loss Available-for-sale securities, realized loss Realized losses United Kingdom, Pounds U.S. dollar/British pound sterling Measurement Input, Expected Dividend Payment [Member] Measurement Input, Expected Dividend Payment [Member] Significant Accounting Policies [Text Block] Accounting Policies Finite-Lived Intangible Asset, Useful Life Estimated useful lives of customer relationships, development technology, trade name, and deferred tax liability Weighted average estimated useful life Share Repurchase Program [Axis] Currency [Axis] Currency [Axis] Extended Product Warranty Accrual, Period Increase (Decrease), Total Extended Product Warranty Accrual, Period Increase (Decrease) Revenue deferrals related to extended warranties Vesting [Domain] Vesting [Domain] Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Computation of Basic and Diluted Earnings Per Common Share Attributable to Teradyne Trademarks and Trade Names [Member] Trademarks and tradenames Trademarks and Tradenames Foreign Currency Transaction (Loss), Unrealized Foreign Currency Transaction Loss Unrealized Equity securities unrealized loss Unrealized losses on equity securities Investment, Name [Axis] Earnings Per Share, Basic, Total Earnings Per Share, Basic Basic Earnings per common share attributable to Teradyne - basic Pension and Other Postretirement Benefits Disclosure [Text Block] Retirement Plans Realized Investment Gains (Losses) [Abstract] Realized gains and losses included in 'Other (income) expense, net' in the condensed consolidated statement of operations Foreign currency translation adjustment, net of tax of $0, $0, $0, and $0, respectively Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Foreign currency translation adjustment, net of tax of $0, $0, $0, and $0, respectively Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Schedule of Available-for-Sale Marketable Securities Business Combination, Recognized Asset Acquired, Asset, Current Business Combination, Recognized Asset Acquired, Asset, Current, Total Current assets Revolving Credit Facility [Member] Revolving Credit Facility Finite-Lived Intangible Assets Acquired Total Intangible assets, Fair Value Retirement Plan Type [Domain] Retirement Plan Type [Domain] Liabilities, Current Total current liabilities Automated Test Equipment Technology And Associated Development Team [Member] Automated test equipment technology and associated development team. AET Disposal Group, Including Discontinued Operation, Accounts Payable, Current Accounts payable Debt Conversion Description [Axis] Debt Conversion Description [Axis] Increase (Decrease) in Accounts Receivable Accounts receivable Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Adjustments to reconcile consolidated net income from operations to net cash provided by operating activities: Hedging Designation [Domain] Hedging Designation [Domain] Inventory, Finished Goods, Net of Reserves Finished goods Share Repurchase Program [Domain] Other long-term liabilities Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Consolidation Items [Domain] Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax Total Shareholder Return Performance-Based Restricted Stock Units Total Shareholder Return Performance-Based Restricted Stock Units [Member] TSR Performance-Based Restricted Stock Units Stockholders' Equity Attributable to Parent [Abstract] EQUITY Percentage of excise tax on share repurchases in excess of issuances. Percentage Of Excise Tax On Share Repurchases In Excess Of Issuances Percentage of excise tax on share repurchases in excess of issuances Entity Small Business Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block] Schedule of Notional Amount of Derivatives Hedging Designation [Axis] Hedging Designation [Axis] Retained earnings Retained Earnings (Accumulated Deficit), Total Retained Earnings (Accumulated Deficit) Nature of Operations [Text Block] The Company Credit agreement. Credit Agreement Credit Agreement [Member] Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases Tangible assets acquired and liabilities assumed: Business Combination, Tangible Assets Acquired and Liabilities Assumed [Abstrac] Business combination, tangible assets acquired and liabilities assumed. Other Current Assets [Member] Other Current Assets Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Stock-Based Compensation One point two five percent convertible senior unsecured notes. One Point Two Five Percent Convertible Senior Unsecured Notes [Member] 1.25% Convertible Senior Unsecured Notes Organization, Consolidation and Presentation of Financial Statements [Abstract] Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities Incremental shares from assumed conversion of convertible notes Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax [Abstract] Cash flow hedges: Payments of Dividends, Total Payments of Dividends Dividend payment Dividend payments Prepaid Expense And Other Assets Table [Text Block] Prepaid Expense And Other Assets [Table Text Block] Schedule of Prepayments and other assets Inventory Valuation Reserves Inventory reserves Weighted Average Number of Shares Outstanding, Diluted, Adjustment, Total Weighted Average Number Diluted Shares Outstanding Adjustment Dilutive potential common shares Equity Mutual Funds [Member] Equity Mutual Funds [Member] Mutual Funds Amendment Flag Product and Service [Domain] Product and Service [Domain] Accounting Policies [Table] Accounting policies table. Inventory Disclosure [Text Block] Inventories MultiLane Test Products MultiLane Test Products [Member] MultiLane Test Products. Debt Mutual Funds [Member] Debt Mutual Funds [Member] Debt Mutual Funds Disposal Group, Including Discontinued Operation, Assets, Current Current assets held for sale Total current assets held for sale Entity Address, Postal Zip Code Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Net cash provided by operating activities Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description Intra-Entity Foreign Currency Balance [Line Items] Intercompany Foreign Currency Balance [Line Items] Common Stock [Member] Common Stock Inventory Business Combination, Recognized Asset Acquired, Inventory, Current Weighted average grant date stock price Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Assets for Plan Benefits, Defined Benefit Plan Retirement plans assets Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Schedule of Derivative Instruments in Statement of Financial Position at Fair Value Available for sale debt and equity securities current. Available For Sale Debt And Equity Securities Current Marketable securities Amortization of Debt Discount (Premium) Amortization of debt issuance fees recognized as interest expense Debt Securities, Available-for-sale [Line Items] Schedule of Available-for-sale Securities Foreign Exchange Option [Member] Foreign Exchange Option [Member] Convertible Common Stock [Member] Convertible Common Shares Portion at Fair Value Measurement [Member] [Default] Portion at Fair Value Measurement [Member] Entity Address, Address Line One Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Fair Value of Stock Options Using Assumptions Fair Value Hierarchy and NAV [Axis] Fair Value, Hierarchy Product Warranties Disclosures [Abstract] Earnings Per Share [Abstract] Earnings per common share attributable to Teradyne: Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost Total, cost Singapore, Dollars Singapore dollar/U.S. dollar Supplemental Cash Flow Information [Abstract] Supplementary disclosure of cash flows information: Derivative Asset, Total Derivative Asset Derivative assets Fair value of outstanding contracts Goodwill and Intangible Assets Disclosure [Text Block] Goodwill and Acquired Intangible Assets Statement of Financial Position Location, Balance [Axis] Balance Sheet Location [Axis] Deferred revenue and customer advances undelivered elements and other. Deferred Revenue And Customer Advances Undelivered Elements And Other Customer advances, undelivered elements and other Operating Lease, Right-of-Use Asset Operating lease right-of-use assets, net Debt Securities, Available-for-Sale, Unrealized Loss Position, Total Debt Securities, Available-for-sale, Unrealized Loss Position Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses Increase (Decrease) in Income Taxes Income taxes Net Income (Loss) Attributable to Noncontrolling Interest Net Income (Loss) Attributable to Noncontrolling Interest, Total Less: Net income attributable to noncontrolling interests Inventory Disclosure [Abstract] Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Total Gain (Loss) on Sale of Investments, Total Gain (Loss) on Sale of Investments Losses (gains) on investments Percentage of issued and outstanding shares acquired Percentage of Issued and Outstanding Shares Acquired Percentage of issued and outstanding shares acquired. Document Type S&P 500 constituents volatility-historical [ Member ] S&P 500 Constituents Volatility-Historical. 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Type of Adoption [Domain] Type of Adoption [Domain] Business Combination, Recognized Asset Acquired, Deferred Tax Asset Long-term deferred tax assets Share-based Compensation Award, Tranche One [Member] Share-based Compensation Award, Tranche One Liabilities [Abstract] LIABILITIES Base Rate [Member] Base Rate Goodwill [Line Items] Goodwill [Line Items] Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to effect of tax cuts and jobs act. Effective Income Tax Rate Reconciliation Effect Of Tax Custs And Jobs Act Percent International provisions of the U.S. Tax Cuts and Jobs Act of 2017 Debt Securities, Available-for-Sale, Amortized Cost, Total Debt Securities, Available-for-sale, Amortized Cost Available-for-sale marketable securities, Cost Warrant exercises shares. 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Disposal Group Including Discontinued Operation Net Assets held for sale Net assets held for sale Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Risk-free interest rate Increase (Decrease) in Prepaid Expense and Other Assets Prepayments and other assets Net Income (Loss) Per Common Share [Line Items] Net Income Loss Per Common Share [Line Items] Net Income Loss Per Common Share Restructuring and Related Activities [Abstract] Document Fiscal Year Focus Asia Pacific [Member] Asia Pacific Shareholder Return Award Performance Measurement Period Shareholder Return Award Performance Measurement Period Total shareholder return performance measurement period Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Cash flows from investing activities: Retirement Benefits [Abstract] Accounts Payable, Current, Total Accounts Payable, Current Accounts payable Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Decrease in unrecognised tax benefit due to lapse in statute of limitation Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Realized and Unrealized Gains and Loss Schedule of Net Benefit Costs [Table Text Block] Net Periodic Pension and Postretirement Benefit Costs Pre-tax gain on sale of business Gain on sale of business Gain on sale of a business Gain (Loss) on Disposition of Business Purchase of investment in a business Payments to Acquire Assets, Investing Activities Position [Axis] Position [Axis] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] Amortization of Prior Service Credit Retirement Plans Prior Service Credit Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2026 Gregory Smith [Member] Gregory smith. Gregory Smith Convertible common shares [Member]. Convertible Common Shares [Member] Revision of Prior Period [Domain] Purchase Obligation, Due in Next Twelve Months Purchase commitments less than one year Accounting Standards Update 2020-06 [Member] Fair Value Disclosures [Abstract] Commitments and Contingencies Disclosure [Abstract] Possible Event. Possible Event [Domain] Disposal Group, Including Discontinued Operation, Liabilities Long-term liabilities held for sale Total liabilities held for sale Developed Technology and Customer Relationships Developed Technology And Customer Relationships [Member] Developed technology and customer relationships. Debt Instrument [Axis] Debt Instrument Derivative Instrument [Axis] Derivative Instrument [Axis] Defined Benefit Plan, Interest Cost Interest cost Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Assets, Fair Value Disclosure Assets Total Percentage of ownership attributable to noncontrolling interests Noncontrolling Interest in Joint Ventures Percentage Noncontrolling interest in joint ventures percentage. 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Trade Accounts Receivable Trade Accounts Receivable Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties Accruals related to pre-existing warranties Statement of Income Location, Balance [Axis] Income Statement Location [Axis] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Trading Symbol Fair value of publicly-traded investment in Technoprobe Equity Method Investments, Fair Value Disclosure Intangible Asset, Finite-Lived [Table] Schedule of Finite-Lived Intangible Assets Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost Due within one year, cost Director Director [Member] Payments to acquire available for sale securities debt and equity. Payments to Acquire Available for Sale Securities Debt and Equity Purchases of marketable securities Income loss from continuing operations before equity net earnings of affiliate. Income Loss From Continuing Operations Before Equity Net Earnings of Affiliate Income before equity in net earnings of affiliate Income before equity in net earnings of affiliate Subsequent Event Type [Axis] Subsequent Event Type [Axis] Robotics. Robotics [Member] Robotics Schedule of Finite-Lived Intangible Assets [Table Text Block] Schedule of Amortizable Intangible Assets Disposal Group, Including Discontinued Operation, Prepaid and Other Assets, Current Prepayments Contract manufacturer and supplier prepayments, classified as assets held for sale Employee-related Liabilities, Current, Total Employee-related Liabilities, Current Accrued employees' compensation and withholdings Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Cash flows from financing activities: Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Commitment fee percentage of unused portion of credit facility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Expected life (years) Fair Value, Measurements, Recurring [Member] Fair Value, Measurements, Recurring Soc. Soc [Member] SOC System on-a-Chip Selling and Marketing Expense Selling and Marketing Expense, Total Selling and marketing Equity Components [Axis] Equity Components [Axis] Research and Development Expense (Excluding Acquired in Process Cost) Engineering and development Equity Component [Domain] Equity Component [Domain] Settlement expense Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement, Total Goodwill and Intangible Assets Disclosure [Abstract] Deferred Revenue, Noncurrent, Total Deferred Revenue, Noncurrent Long-term deferred revenue and customer advances Standard and Extended Product Warranty Accrual, Total Standard and Extended Product Warranty Accrual Balance at end of period Balance at beginning of period Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block] Summary of Allocation of Total Purchase Price Business Combination [Axis] Business Acquisition [Axis] Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost Due after 5 years through 10 years, cost Statement of Comprehensive Income [Abstract] Corporate Joint Venture [Member] MultiLane Test Products ("MLTP") Intra-Entity Foreign Currency Balance [Table] Schedule of Intercompany Foreign Currency Balance [Table] Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits, Total Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits Retirement plans contributions Maximum [Member] Maximum Impairment of Intangible Assets (Excluding Goodwill) Impairment of Intangible Assets (Excluding Goodwill), Total Impairment of intangible assets Financial and Nonfinancial Liabilities, Fair Value Disclosure Liabilities Total Designated as Hedging Instrument [Member] Range [Axis] Range Finite-Lived Intangible Assets, Accumulated Amortization Accumulated Amortization Prepaid Expense, Current Total prepayments Prepayments Common Stock, Value, Issued Common stock, $0.125 par value, 1,000,000 shares authorized; 157,245 and 161,722 shares issued and outstanding at September 28, 2025, and December 31, 2024, respectively Common stock, $0.125 par value, 1,000,000 shares authorized; 156,378 and 156,088 shares issued and outstanding at June 28, 2026, and December 31, 2025, respectively Income Tax Holiday, Aggregate Dollar Amount Income Tax Holiday, Aggregate Dollar Amount Percentage of alternative minimum tax. Percentage of Alternative Minimum Tax Percentage of alternative minimum tax Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statement of Operations Equity, Including Portion Attributable to Noncontrolling Interest Total equity Balance Balance Tax Credit Carryforward [Axis] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Schedule of Estimated Intangible Assets Amortization Expense Other Nonoperating Income (Expense) [Abstract] Non-operating (income) expense: Long-term Debt, Term Term of revolving credit facility Available incremental amount under the credit facilitynNot to exceed percentage of consolidated EBIDTA. Available Incremental Amount Under The Credit Facility Not To Exceed Percentage Of Consolidated EBIDTA Available Incremental Amount Under The Credit Facility Not To Exceed Percentage Of Consolidated EBIDTA Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected historical volatility Volatility-historical Less: comprehensive income attributable to noncontrolling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest, Total Accumulated net unrealized losses on cash flow hedges. Accumulated Net Unrealized Losses On Cash Flow Hedges [Member] Unrealized (Losses) Gains on Cash Flow Hedges Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class Payments Related to Tax Withholding for Share-based Compensation Payments related to net settlement of employee stock compensation awards Schedule of available for sale securities reconciliation. Schedule Of Available For Sale Securities Reconciliation [Table] Schedule of Available-for-sale Securities Lender Name [Axis] Repayments of Convertible Debt Payments of convertible debt principal Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value Total, fair market value Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period Warrant exercises. Warrant Exercises Warrant exercises Revenue from Contract with Customer [Text Block] Revenue Business Combination [Table] London interbank offered rate. London Interbank Offered Rate [Member] London Interbank Offered Rate (LIBOR) Entity Registrant Name Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Accrued interest and penalties Debt Disclosure [Text Block] Debt Marketable Securities. Marketable securities [Member] Marketable securities Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Available-for-sale marketable securities, Unrealized (Loss) Accrued Income Taxes, Noncurrent Long-term incomes taxes payable Finite-Lived Intangible Assets, Amortization Expense, Year Two 2027 Deferred Revenue Arrangement [Line Items] Other Nonoperating Income (Expense), Total Other Nonoperating Income (Expense) Other (income) expense, net Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Subsequent Events [Abstract] Employees of the entity. Employees [Member] Employees Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value Noncontrolling interests Fair value of noncontrolling interests Finite-Lived Intangible Assets, Amortization Expense, Year Three 2028 Income tax expense Income tax provision Income Tax Expense (Benefit), Total Income Tax Expense (Benefit) Measurement Frequency [Axis] Measurement Frequency [Axis] Common Stock, Dividends, Per Share, Cash Paid Sales [Member] IST. IST IST [Member] Non-Rule 10b 5-1 Arrangement Modified Flag Non-Rule 10b5-1 Arrangement Modified Non-Rule 10b 5-1 arrangement modified flag. Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award Subsidiary, Ownership Percentage, Noncontrolling Owner Percentage of fair value of noncontrolling interests Entity Common Stock, Shares Outstanding Accumulated Other Comprehensive Income (Loss), Net of Tax, Total Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive loss (gain) Accumulated other comprehensive income (loss) Consolidation Items [Axis] Convertible Debt [Table Text Block] Schedule of Interest Expense on Teradyne's Senior Notes Payments to Acquire Property, Plant, and Equipment, Total Payments to Acquire Property, Plant, and Equipment Purchases of property, plant and equipment Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Restricted stock unit awards granted Assets Total assets Total assets Income Statement [Abstract] Retirement Plan Name [Domain] Retirement Plan Name [Domain] Noncontrolling Interests Noncontrolling Interests [Policy Text Block] Noncontrolling interests. Restructuring Cost [Table] Schedule of Restructuring and Related Costs Corporate And Eliminations [Member] Corporate and Eliminations [Member] Corporate And Eliminations Rule 10b51 arr modified flag. Rule 10b51 Arr Modified Flag Net actuarial loss (gain) Defined Benefit Plan, Amortization of Gain (Loss) Retirement plan actuarial losses (gains) Deferred Income Tax Expense (Benefit), Total Deferred Income Tax Expense (Benefit) Deferred taxes Acquisition and divestiture expenses. Acquisition And Divestiture Expenses Acquisition and divestiture expenses Business Combinations [Abstract] Restructuring, Settlement and Impairment Provisions, Total Restructuring, Settlement and Impairment Provisions Restructuring and other Restructuring and other—employee severance Earnings Per Share, Diluted, Total Earnings Per Share, Diluted Diluted Earnings per common share attributable to Teradyne - diluted Schedule of Segment Reporting Information, by Segment [Table Text Block] Segment Information Position [Domain] Position [Domain] Income Tax Disclosure [Table] Income Tax Disclosure [Table] Income Tax Disclosure [Table] Operating Segments [Member] Operating Segments Finite-Lived Intangible Assets, Amortization Expense, Year Five 2030 Long-term Contract with Customer [Member] Exercise of convertible notes hedge call options. Exercise Of Convertible Notes Hedge Call Options Exercise of convertible notes hedge call options (in shares) Exercise of convertible notes hedge call options (in shares) Non U S Subsidiaries [Member] Non U S Subsidiaries [Member] Non-United States Subsidiaries The tax effect from accumulated appreciation or loss, in value of the total of unsold securities at the end of an accounting period. Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Tax Unrealized (losses) gains on marketable securities, tax Title and Position [Domain] Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value Available for sale securities with out contractual maturity date Contract manufacturer and supplier prepayments. Contract Manufacturer and Supplier Prepayments Contract manufacturer and supplier prepayments Product Test [Member] Product test. Product Test Disposal Group, Including Discontinued Operation, Assets Long-term assets held for sale Total assets held for sale Assets held for sale City Area Code Dividends Per Share Dividends Per Share Estimated annual dividend amount per share Other Comprehensive Income (Loss), Net of Tax Other comprehensive income (loss) Other comprehensive income (loss) Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Remeasurement due to Settlement Reduction in pension benefit obligation and pension assets due to remeasurement Stock issued during period shares sale of stock and exercise of stock options. Stock Issued During Period Shares Sale Of Stock And Exercise Of Stock Options Exercise of stock options Proceeds from borrowings on revolving credit facility Proceeds from Lines of Credit Proceeds from Lines of Credit, Total Richard Burns [Member] Richard Burns. Richard Burns Income Tax Examination, Penalties and Interest Expense, Total Income Tax Examination, Penalties and Interest Expense Interest and penalties related to income tax, expense (benefit) Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Business Acquisition [Line Items] Defined Benefit Plan [Table] Schedule of Defined Benefit Plans Disclosures Prepaid maintenance and other services. Prepaid Maintenance And Other Services Prepaid maintenance and other services Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax Unrealized (losses) gains, net Unrealized (losses) gains, net Less: Reclassification adjustment for (gains) losses included in net income, net of tax of $0, $(869), $(500) and $(441) respectively Less: Reclassification adjustment for losses (gains) included in net income, net of tax of $0, $66, $0, and $(100), respectively Minimum Years Of Service For Eligible Employees Of Postretirement Plans Minimum Years Of Service For Eligible Employees Of Postretirement Plans Minimum years of service for retirement to be eligible for PRSUs Dividends, Cash, Total Dividends, Cash Cash dividends Dividend payment Foreign exchange forward and option contracts. Foreign Exchange Forward And Option Contracts [Member] Foreign Exchange Forward and Option Contracts [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Disposal Group Name [Axis] Retirement Plan Name [Axis] Retirement Plan Name [Axis] Financial Instruments and Fair Value [Table] Financial Instruments and Fair Value [Table] Financial Instruments and Fair Value [Table] Deferred Revenue Disclosure [Abstract] Property, Plant and Equipment, Net, Total Property, Plant and Equipment, Net Property, plant and equipment, net Impairment of Intangible Assets, Finite-lived Impairment of intangible assets Defined benefit plan special termination benefit obligation. Defined Benefit Plan Special Termination Benefit Obligation Special termination benefits Operating Income (Loss) Income from operations Goodwill, Foreign Currency Translation, Gain (Loss) Foreign currency translation adjustment Retained Earnings [Member] Retained Earnings Japan, Yen U.S. dollar/Japanese yen Share-Based Payment Arrangement, Noncash Expense, Total Share-based Compensation Stock-based compensation Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax, Total Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Foreign currency translation adjustments, tax Foreign Currency [Abstract] Amortization of prior service credit, net of tax Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, Tax Operating Lease, Liability, Noncurrent Long-term operating lease liabilities Fair Value, Inputs, Level 1 [Member] Quoted Prices in Active Markets for Identical Instruments (Level 1) The tax effect from accumulated adjustment, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains (losses). Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Foreign currency translation adjustments, tax Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Net cash used for financing activities Collateral [Domain] Developed Technology Rights [Member] Developed technology Developed Technology Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value Due after 5 years through 10 years, fair market value The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income. Also includes customer advance payments represent a part or a full amount of a contractually due sum that is paid in advance of the delivery of goods or services. Deferred Revenue And Customer Advances, Current Deferred revenue and customer advances Derivative Contract [Domain] Derivative Contract [Domain] Goodwill [Table] Schedule of Goodwill [Table] Schedule of segment reporting information by segment charges. Schedule Of Segment Reporting Information By Segment Charges [Table Text Block] Schedule of Segment Reporting Information by Segment Charges Finite Lived Intangible Assets, Foreign Currency Translation Gain (Loss) Foreign Currency Translation Adjustment Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Interest income (expense) Less: Reclassification adjustment for (gains) losses included in net income, net of tax of $16, $6, $12, $27, respectively Less: Reclassification adjustment for (gains) losses included in net income, net of tax of $16, $6, $12, $27, respectively Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] US Government Corporations and Agencies Securities [Member] U.S. Government Agency Securities Corporate Debt Securities [Member] Corporate Debt Securities Income Tax Jurisdiction [Domain] Income Tax Authority [Domain] Entity Interactive Data Current Increase (Decrease) in Contract with Customer, Liability Deferred revenue and customer advances Statement of Income Location, Balance [Domain] Income Statement Location [Domain] Prepaid expense. Prepaid Expense [Member] Prepayments Prepayments Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Cash flows from operating activities: Transferred over Time [Member] Over Time Repayments of borrowings on revolving credit facility Repayments of Lines of Credit Payment for Severance Cost Payment for severance cost. Severance payments Recently issued accounting pronouncements. Recently Issued Accounting Pronouncements [Text Block] Recently Issued Accounting Pronouncements Standard and Extended Product Warranty Accrual, Period Increase (Decrease), Total Standard and Extended Product Warranty Accrual, Period Increase (Decrease) Product warranty accrual Defined Benefit Plan, Benefit Obligation, Payment for Settlement Settlement expense Cumulative Effect, Period of Adoption [Domain] Entity Tax Identification Number Revenues [Abstract] Revenues: Share Price Stock price Prepaid Taxes Prepaid taxes Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Proceeds from maturities of marketable securities Profit Before Income and Tax Performance Based Restricted Stock Units [Member] Profit Before Income and Tax Performance Based Restricted Stock Units [Member] PBIT Performance-Based Restricted Stock Units Local Phone Number Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Total net periodic pension cost Sanjay Mehta [Member] Sanjay Mehta. Sanjay Mehta Technoprobe. Technoprobe [Member] Technoprobe [Member] Revenue, Remaining Performance Obligation, Percentage Revenue, Remaining Performance Obligation, Percentage Line of Credit Facility, Interest Rate Description Line of Credit Facility, Interest Rate Description China, Yuan Renminbi Chinese yuan/U.S. dollar Mercedes Johnson [Member] Mercedes Johnson. Mercedes Johnson Accounting Policies [Abstract] Other Current Liabilities [Member] Other Current Liabilities Other comprehensive (loss) gain before reclassifications, net of tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Balance Sheet Locations. Balance Sheet Locations [Domain] Balance Sheet Location [Domain] Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Unrealized (Losses) Gains on Marketable Securities Available for sale debt and equity securities non current. Available For Sale Debt And Equity Securities Non Current Marketable securities Cash and Cash Equivalents [Member] Cash and Cash Equivalents Class of Stock [Domain] Commercial Paper [Member] Commercial Paper Goodwill, Impaired, Accumulated Impairment Loss Accumulated impairment losses Point in Time Transferred at Point in Time [Member] Entity Emerging Growth Company Deferred revenue and customer advances maintenance service and training. Deferred Revenue And Customer Advances Maintenance Service And Training Maintenance, service and training Revision of Prior Period, Accounting Standards Update, Adjustment [Member] Total purchase price Total purchase price Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill Tax Credit Carryforward, Name [Domain]