Patents and other assets, net PatentAndOtherAssetsNet Level 3 Fair Value, Inputs, Level 3 [Member] Stock-based compensation expense related to stock options, employee stock purchases and restricted stock APIC, Share-based Payment Arrangement, Increase for Cost Recognition Total current liabilities Liabilities, Current Equity investment losses were considered to be other than temporary Other than Temporary Impairment Losses, Investments Indefinite-lived intangible assets Indefinite-lived Intangible Assets (Excluding Goodwill) Germany GERMANY Restricted period, maximum, in years ShareBasedCompensationRestrictedPeriod Adoption of New Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] COST OF GOODS SOLD Cost of Goods and Services Sold Current Fiscal Year End Date Current Fiscal Year End Date Issuance of common stock from stock plan transactions Proceeds from Issuance of Common Stock Diluted weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Entity Address, Postal Zip Code Entity Address, Postal Zip Code Fixed Income Securities Fixed Income Securities [Member] Lease liabilities Assets And Liabilities, Lessee [Table Text Block] Assets And Liabilities, Lessee CASH FLOWS (USED FOR) FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Issuance of common stock from stock plan transactions Stock Issued During Period, Value, New Issues Other Segment OtherSegmentMember PLANT AND EQUIPMENT—NET Property, Plant and Equipment, Net Accumulated  Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] (Gain) on sale of investments Gain on Sale of Investments Total assets Assets Entity Shell Company Entity Shell Company Total Operating Lease, Liability Cover [Abstract] Document Type Document Type Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Subsequent Event Subsequent Event [Member] Equity Interest Type [Axis] Equity Interest Type [Axis] Work-in-process Inventory, Work in Process, Gross Share-based Payment Arrangement [Abstract] Increase in borrowing rate Debt Instrument, Interest Rate, Increase (Decrease) Restricted Stock Restricted Stock [Member] Accounts receivable, net Increase (Decrease) in Accounts Receivable 2023 Lessee, Operating Lease, Liability, Payments, Due Year Four CURRENT LIABILITIES Liabilities, Current [Abstract] Automotive Products AutomotiveProductsMember Due over five years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Years, Fair Value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Years, Fair Value Aggregate Unrealized Losses, Loss duration greater than one year Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Financial Instrument [Axis] Financial Instrument [Axis] Segment Reporting Segment Reporting Disclosure [Text Block] Equity [Abstract] Other Products OtherProductsMember Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Document Quarterly Report Document Quarterly Report Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] CASH AND CASH EQUIVALENTS, beginning of period CASH AND CASH EQUIVALENTS, end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Debt Instrument [Line Items] Debt Instrument [Line Items] Class of Stock [Domain] Class of Stock [Domain] Due within one year Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Entity File Number Entity File Number Option vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Segments [Axis] Segments [Axis] Document Fiscal Period Focus Document Fiscal Period Focus Financial Instruments [Domain] Financial Instruments [Domain] Other comprehensive income, net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Interest expense annual increase Interest Expense, Debt, Annual Increase Interest Expense, Debt, Annual Increase Other comprehensive income before tax: Other Comprehensive Income (Loss), before Tax [Abstract] Product and Service [Domain] Product and Service [Domain] Weighted-Average Assumptions For The Employee Stock Option Plan Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Income from operations Income from operations Operating Income (Loss) Schedule of Amortized Cost, Unrealized Gains And Losses, And Market Value of Investment Securities Unrealized Gain (Loss) on Investments [Table Text Block] Employee Stock Option Plan EmployeeStockOptionPlanMember Goodwill Goodwill Segments [Domain] Segments [Domain] Statement [Line Items] Statement [Line Items] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Basic (in dollars per share) Net Income per share - Basic (in dollars per share) Earnings Per Share, Basic Inventories Inventory Disclosure [Text Block] Cash Dividends Declared per Share (in dollars per share) Dividends declared (in dollars per share) Common Stock, Dividends, Per Share, Declared Net current-period change Comprehensive Income (Loss), Net of Tax, Attributable to Parent Plan Name [Axis] Plan Name [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Adjustments to reconcile net income to net cash provided by operating activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Statement of Stockholders' Equity [Abstract] Amendment Flag Amendment Flag Exclusive Licensing Agreement Licensing Agreements [Member] Investment Securities Stated at Fair Value Fair Value, Assets Measured on Recurring Basis [Table Text Block] HomeLink Modules HomeLinkModulesMember Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding INCOME BEFORE PROVISION FOR INCOME TAXES Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Level 1 Fair Value, Inputs, Level 1 [Member] Class of Stock [Axis] Class of Stock [Axis] Dividends declared Dividends Equity Stockholders' Equity Note Disclosure [Text Block] Plan Name [Domain] Plan Name [Domain] Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Raw materials Inventory, Raw Materials, Gross Local Phone Number Local Phone Number Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Increase in quarterly dividend rate (in dollars per share) Increase in Cash Dividend Rate Accrued liabilities, excluding dividends declared and short-term debt Increase (Decrease) in Accrued Liabilities Total future minimum lease payments Lessee, Operating Lease, Liability, Payments, Due Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Total other income Nonoperating Income (Expense) Prepaid expenses and other Prepaid Expense and Other Assets, Current Total current assets Assets, Current Entity Current Reporting Status Entity Current Reporting Status Government Securities US Treasury Securities [Member] New Accounting Pronouncements and Changes in Accounting Principles [Abstract] New Accounting Pronouncements and Changes in Accounting Principles [Abstract] NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect NET INCOME Net Income Net Income (Loss) Attributable to Parent Unrealized gains on debt securities, net Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, before Tax Short-Term Investments Short-term Investments [Member] Common Stock Common Stock [Member] CURRENT ASSETS Assets, Current [Abstract] Amortization expense, 2024 Finite-Lived Intangible Assets, Amortization Expense, Year Five Leases [Abstract] Omnibus Incentive Plan Omnibus Incentive Plan [Member] Omnibus Incentive Plan Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Total net reclassifications for the period Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Product and Service [Axis] Product and Service [Axis] Entity Small Business Entity Small Business Commitments and Contingencies Disclosure [Abstract] Entity Filer Category Entity Filer Category Letter of Credit Letter of Credit [Member] Compensation expense for share-based payments Share-based Payment Arrangement, Expense Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total liabilities and shareholders’ investment Liabilities and Equity OTHER ASSETS Assets, Noncurrent [Abstract] Entity Address, City or Town Entity Address, City or Town Income Tax Disclosure [Abstract] Other comprehensive income, before tax Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Certificates of Deposit Certificates of Deposit [Member] Amortization expense Restricted Stock or Unit Expense Patents and Other Intangible Assets PatentsandOtherIntangibleAssetsMember Current portion of long-term debt Long-term Debt, Current Maturities Other Non-Current Liabilities Operating Lease, Liability, Noncurrent OPERATING EXPENSES: Operating Expenses [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Equity Incentive Plans Share-based Payment Arrangement [Member] SHAREHOLDERS’ INVESTMENT Stockholders' Equity Attributable to Parent [Abstract] Document Fiscal Year Focus Document Fiscal Year Focus Sales proceeds Proceeds from Sale of Debt Securities, Available-for-sale Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Weighted average grant-date fair value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Vaporsens Inc Vaporsens Inc [Member] Vaporsens Inc Subsequent Event Subsequent Events [Text Block] Finite-lived intangible asset, useful life (in years) Finite-Lived Intangible Asset, Useful Life Intangible assets, gross Intangible Assets, Gross (Excluding Goodwill) Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Shares granted (in shares) Employee Stock Ownership Plan (ESOP), Number of Allocated Shares Award Type [Axis] Award Type [Axis] Change in operating assets and liabilities: Increase (Decrease) in Operating Assets [Abstract] Dividends declared Dividends, Common Stock, Cash Automotive Products AutomotiveProductsSegmentMember Other income (loss), net Other Nonoperating Income (Expense) Subsequent Events [Abstract] Cost Debt Securities, Available-for-sale, Amortized Cost, Current Accumulated other comprehensive income (loss) Accumulated other comprehensive gain (loss), end of period Accumulated Other Comprehensive Income (Loss), Net of Tax Repurchases of common stock Stock Repurchased During Period, Value HomeLink Trade Names and Trademarks Trademarks and Trade Names [Member] Amounts Reclassified from Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Geographical [Axis] Geographical [Axis] Retained  Earnings Retained Earnings [Member] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Swing Loans SwingLoansMember Shares issued under the Omnibus plan Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period Leases Lessee, Operating Leases [Text Block] Document Period End Date Document Period End Date Statement [Table] Statement [Table] Entity Registrant Name Entity Registrant Name Equity Interest Issued or Issuable, Type [Domain] Equity Interest Issued or Issuable, Type [Domain] Purchases Payments to Acquire Debt Securities, Available-for-sale Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Number of shares authorized (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Maximum Maximum [Member] 2022 Lessee, Operating Lease, Liability, Payments, Due Year Three Option expiration period Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Total Debt Securities, Available-for-sale Corporate Bonds Corporate Bond Securities [Member] Retained earnings Retained Earnings (Accumulated Deficit) Repurchases of common stock Payments for Repurchase of Common Stock Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Entity Tax Identification Number Entity Tax Identification Number Principal amount Debt Instrument, Face Amount Diluted (in dollars per share) Net Income per share - Diluted (in dollars per share) Earnings Per Share, Diluted Long-Term Investments Other Long-term Investments [Member] Equity interest investment Business Acquisition, Equity Interest Issued or Issuable, Value Assigned Trading Symbol Trading Symbol Minimum Minimum [Member] Investments, Debt and Equity Securities [Abstract] Amortization expense, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Two Change in deferred income taxes Deferred Income Tax Expense (Benefit) Range [Domain] Statistical Measurement [Domain] Homelink Technology Developed Technology Rights [Member] Plant and equipment additions Payments to Acquire Productive Assets Net decrease in period (in shares) NetDecreaseinCommonStockSharesfromSharesIssuedinShareBasedCompensationandSharesRepurchased Net cash (used for) financing activities Net Cash Provided by (Used in) Financing Activities Realized gain (loss) on sale of securities and interest rate swap Equity Securities, FV-NI, Realized Gain (Loss) Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Inventory Disclosure [Abstract] PROVISION FOR INCOME TAXES Provision for income taxes Income Tax Expense (Benefit) Stock-Based Compensation Plans Share-based Payment Arrangement [Text Block] Investments and Cash Investments and Cash Loss on sale of investments Loss on Sale of Investments 2021 Lessee, Operating Lease, Liability, Payments, Due Year Two Amounts reclassified from accumulated other comprehensive income Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax ESPP discount rate Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date Revenue from Contract with Customer [Abstract] OTHER NON-CURRENT LIABILITIES Other Liabilities, Noncurrent Number of plans SharebasedCompensationArrangementbySharebasedPaymentAwardNumberOfPlans HomeLink® HomeLinkMember Employee Stock Purchase Plan EmployeeStockPurchasePlanMember Windows Products WindowsProductsMember Loss on disposal of assets Loss on Disposition of Assets Loss on Disposition of Assets City Area Code City Area Code Other Other Segments [Member] Prepaid expenses and other Increase (Decrease) in Prepaid Expense and Other Assets Intangible assets, net Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Title of 12(b) Security Title of 12(b) Security Automotive Segment AutomotiveSegmentMember Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Long-term investments Long-term Investments EARNINGS PER SHARE: Earnings Per Share [Abstract] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Asset-backed Securities Asset-backed Securities [Member] Income tax impact related to components of other comprehensive income Other Comprehensive Income (Loss), Tax Unrealized gains (losses) on available-for-sale debt securities AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] Future minimum lease payments Lessee, Operating Lease, Liability, Maturity [Table Text Block] interest rate Debt Instrument, Interest Rate During Period Reallocation of undistributed earnings Participating Securities, Distributed and Undistributed Earnings (Loss), Diluted ASSETS Assets [Abstract] Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Weighted average remaining lease term Operating Lease, Weighted Average Remaining Lease Term Schedule of AOCI Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Amortization expense, 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Three CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Total operating expenses Operating Expenses Performance Shares Performance Shares [Member] Additional weighted average dilutive common stock equivalents (in shares) Weighted Average Number Diluted Shares Outstanding Adjustment Due between one and five years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value Schedule of Automotive and Other Segment Reporting Schedule of Segment Reporting Information, by Segment [Table Text Block] Segment Reporting [Abstract] Less imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Finite-lived intangible assets, net Finite-Lived Intangible Assets, Net Debt Disclosure [Abstract] Schedule of Inventories Schedule of Inventory, Current [Table Text Block] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Range [Axis] Statistical Measurement [Axis] Weighted average discount rate Operating Lease, Weighted Average Discount Rate, Percent Accumulated other comprehensive income (loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] NET SALES Revenue Revenue from Contract with Customer, Including Assessed Tax Comprehensive Income Comprehensive Income (Loss) Note [Text Block] Aggregate Fair Value, Loss duration greater than one year Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer Accounts payable Increase (Decrease) in Accounts Payable Statement of Financial Position [Abstract] Repurchases of common stock (in shares) Stock repurchased (in shares) Stock Repurchased During Period, Shares Debt and Financing Arrangements Debt Disclosure [Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Intangible Assets Schedule of Intangible Assets and Goodwill [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Finite-lived intangible assets, accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Statement of Cash Flows [Abstract] Entity Central Index Key Entity Central Index Key Unrecognized compensation cost Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Other Other Debt Obligations [Member] Activity in available-for-sale securities: Proceeds from Sale and Maturity of Debt Securities, Available-for-sale [Abstract] Entity Emerging Growth Company Entity Emerging Growth Company Selling, general & administrative Selling, General and Administrative Expense Investment income Investment Income, Nonoperating Accrued Liabilities Operating Lease, Liability, Current Stock-based compensation expense related to employee stock options, employee stock purchases and restricted stock Share based compensation expense Share-based Payment Arrangement, Noncash Expense Schedule of Earnings Per Share Basic And Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Restricted Stock Plan RestrictedStockPlanMember 2020 (excluding the three months ended March 31, 2020) Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year Level 2 Fair Value, Inputs, Level 2 [Member] Income Taxes Income Tax Disclosure [Text Block] Adoption of New Accounting Pronouncements New Accounting Pronouncements and Changes in Accounting Principles [Text Block] LIABILITIES AND SHAREHOLDERS’ INVESTMENT Liabilities and Equity [Abstract] Common stock issued under stock compensation plan (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Total other assets Other Assets, Noncurrent Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax Organization, Consolidation and Presentation of Financial Statements [Abstract] Long-term debt Long-term Debt Amortization expense, 2020 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year Amortization expense, 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Four Remaining lease terms Lessee, Operating Lease, Remaining Lease Term Lessee, Operating Lease, Remaining Lease Term Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Reclassifications out of other comprehensive income Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Proceeds from borrowings on Credit Agreement Proceeds from Issuance of Long-term Debt Technology investments Equity Securities without Readily Determinable Fair Value, Amount 2024 Lessee, Operating Lease, Liability, Payments, Due Year Five Additional  Paid-In Capital Additional Paid-in Capital [Member] Revenue Revenue from Contract with Customer [Text Block] DEFERRED INCOME TAXES Deferred Income Tax Liabilities, Net Existing Customer Platforms Customer Contracts [Member] U.S. UNITED STATES Market Value Investments, Fair Value Disclosure Finished goods Inventory, Finished Goods, Gross Entity Address, Address Line One Entity Address, Address Line One Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Municipal Bonds Municipal Bonds [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Gross profit Gross Profit Geographical [Domain] Geographical [Domain] Cash paid to acquire business Payments to Acquire Businesses, Gross Entity Address, State or Province Entity Address, State or Province Automotive Mirrors & Electronics AutomotiveMirrorsElectronicsMember Business Acquisition [Axis] Business Acquisition [Axis] Investments Classified by Contractual Maturity Date Investments Classified by Contractual Maturity Date [Table Text Block] Aggregate Unrealized Losses, Loss duration less than one year Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Net cash (used for) investing activities Net Cash Provided by (Used in) Investing Activities Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Aggregate Fair Value, Loss duration less than one year Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value Purchase price of acquisition Business Combination, Consideration Transferred Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Proceeds from sale of plant and equipment Proceeds from Sale of Property, Plant, and Equipment Business Acquisition [Line Items] Business Acquisition [Line Items] Accounts payable Accounts Payable, Current Other Comprehensive (loss) income before reclassifications Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Reclassification Out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Accrued liabilities Accrued Liabilities, Current Entity Interactive Data Current Entity Interactive Data Current Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding OTHER INCOME (LOSS) Investment Income, Nonoperating [Abstract] Inventories Total Inventory Inventory, Net Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Interest expense Interest Expense, Debt Less: Allocated to participating securities Participating Securities, Distributed and Undistributed Earnings (Loss), Basic Earnings Per Share Earnings Per Share [Text Block] Other OtherCountriesMember Award Type [Domain] Award Type [Domain] Decrease in other assets Increase (Decrease) in Other Operating Assets Contingencies Commitments and Contingencies Disclosure [Text Block] Japan JAPAN Revolving Facility Revolving Credit Facility [Member] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Issuance of common stock from stock plan transactions (in shares) Stock Issued During Period, Shares, New Issues Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax Additional borrowings available Debt Instrument Additional Borrowings Available Face Amount Fire Protection Products FireProtectionProductsMember Cash dividends paid Payments of Ordinary Dividends, Common Stock Indefinite-lived Intangible Assets by Major Class [Axis] Indefinite-lived Intangible Assets [Axis] Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Investments [Domain] Investments [Domain] 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] Total liabilities Liabilities Common stock Common Stock, Value, Issued Maturities and calls Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Engineering, research and development Research and Development Expense Statement of Comprehensive Income [Abstract] Inventories Increase (Decrease) in Inventories Net Income available to common shareholders Net Income (Loss) from Continuing Operations Available to Common Shareholders, Basic Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Basic weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Investments [Abstract] AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Shares approved (in shares) Employee Stock Ownership Plan (ESOP), Shares in ESOP Equity Components [Axis] Equity Components [Axis] Total shareholders’ investment Balance at beginning of period Balance at end of period Stockholders' Equity Attributable to Parent Amortization expense Amortization of Intangible Assets Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Schedule of Unrealized Loss on Investments Schedule of Unrealized Loss on Investments [Table Text Block] (Gain) on disposal of assets Gain on Disposal of Assets Gain on Disposal of Assets Aggregate Unrealized Losses, Total Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss Investments Fair Value Disclosures [Text Block] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Foreign currency translation adjustments Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Depreciation and amortization Depreciation, Depletion and Amortization Investment Type [Axis] Investment Type [Axis] Finite-lived intangible assets, gross Finite-Lived Intangible Assets, Gross Cash & Cash Equivalents Cash and Cash Equivalents, Fair Value Disclosure Security Exchange Name Security Exchange Name Shares related to stock plans not included in diluted average common shares outstanding because their effect would be anti-dilutive (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount ESPP discount rate recognized as compensation expense Share-Based Compensation Arrangement By Share Based Payment Award, Discount Recognized As Compensation Expense Initial investment in Vaporsens Equity Method Investments Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Additional paid-in capital Additional Paid in Capital, Common Stock Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Equity Component [Domain] Equity Component [Domain] Expected term of options Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Document Transition Report Document Transition Report Short-term investments Short-term Investments CASH FLOWS (USED FOR) INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Aggregate Fair Value, Total Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value Net Income available to common shareholders - Diluted Net Income (Loss) Available to Common Stockholders, Diluted Credit Agreement Line of Credit [Member] Mexico MEXICO Gentex Patents Patents [Member] Income Statement [Abstract]