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Operating leases belfa_PaymentForCustomsDutiesAndImposedFinesAndPenalties Payment for Customs Duties and Imposed Fines and Penalties The amount of cash outflow for payment for customs duties and imposed fines and penalties. Asset Class [Axis] EOS Claim From Principal Commissioner of Customs [Member] Related to EOS claim from principal commissioner of customs. belfa_BusinessAcquisitionGoodwillTaxDeductiblePeriod Business Acquisition, Goodwill, Tax Deductible Period (Year) The period of time for which goodwill arising from a business combination will be deductible for tax purposes. 2027, operating leases 2026, operating leases us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) belfa_CustomsDutiesAndImposedFines Customs Duties and Imposed Fines The value of customs duties and imposed fines. 2029, operating leases belfa_LoansAndLeasesReceivableInterestRate Loans and Leases Receivable, Interest Rate The interest rate for loans and leases receivable. belfa_PaymentsToAcquireBusinessesNetOfAdjustments Payments to Acquire Businesses, Net of Adjustments The cash outflow associated with the acquisition of business during the period after giving effect to estimated adjustments taken at closing. us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) 2028, operating leases Schedule of Maturities of Long-Term Debt [Table Text Block] Measurement Frequency [Axis] Commitments and Contingencies Disclosure [Text Block] Fair Value Hierarchy and NAV [Axis] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Common stock, shares outstanding (in shares) Award Type [Domain] Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Common stock, shares authorized (in shares) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Common Class B [Member] Schedule of Accrued Liabilities [Table Text Block] belfa_DefinedContributionPlanEmployerMatchingContributionPercentOfMatchFirst1EmployeeContribution Defined Contribution Plan, Employer Matching Contribution, Percent Of Match, First 1% Employee Contribution Percentage employer matches of the employee's first 1% contribution matched. Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Common Stock belfa_PercentageOfParticipantsAnnualBaseSalaryReceivedByBeneficiaryOneYearFromDateOfDeath Percentage of Participant's Annual Base Salary Received by Beneficiary, One Year From Date of Death The percentage of participant's annual base salary received by beneficiary for one year from date of death. belfa_DefinedBenefitPlanNumberOfMonthlyPayments Defined Benefit Plan, Number of Monthly Payments Refers to number of monthly payments an employee is entitled to receive under the defined benefit plan. Amortization of ROU assets - finance leases Schedule of Inventory, Current [Table Text Block] Gross profit % Represents percentage of gross profit. belfa_PercentageOfParticipantsAnnualBaseSalaryReceivedByBeneficiaryFollowingFourYearsFromDateOfDeath Percentage of Participant's Annual Base Salary Received by Beneficiary, Following Four Years From Date of Death The percentage of participant's annual base salary received by beneficiary for years two through five following date of death. us-gaap_FinanceLeaseLiability Finance leases, Present value of lease liabilities belfa_LineOfCreditFacilityPercentageOfCapitalStockOfForeignSubsidiariesCollateralizedSecurity Line of Credit Facility, Percentage of Capital Stock of Foreign Subsidiaries Collateralized Security The percentage of issued and outstanding shares of the capital stock of foreign subsidiaries given as collateralized security to line of credit. us-gaap_PolicyTextBlockAbstract Accounting Policies belfa_DefinedBenefitPlanPercentageOfAverageBaseCompensationFiveConsecutiveYearsNormalRetirement Defined Benefit Plan, Percentage of Average Base Compensation Five Consecutive Years, Normal Retirement The percentage of average base compensation of the highest five consecutive years for normal retirement under defined benefit plan. us-gaap_ProductWarrantyExpense Product Warranty Expense belfa_DefinedContributionPlanEmployerMatchingContributionPercentOfMatchNext5EmployeeContribution Defined Contribution Plan, Employer Matching Contribution, Percent of Match, Next 5% Employee Contribution Percentage employer matches of the employee's next 5% contribution matched. us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements us-gaap_TableTextBlock Notes Tables Lease accounting Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from lease accounting. Comprehensive Income (Loss) Note [Text Block] Finance leases, Thereafter 2030, finance leases us-gaap_ComprehensiveIncomeNetOfTax Comprehensive income attributable to Bel shareholders 2026, finance leases us-gaap_FinanceLeaseLiabilityNoncurrent Other long-term liabilities us-gaap_FinanceLeaseLiabilityPaymentsDue Finance leases, Total undiscounted cash flows us-gaap_FinanceLeaseLiabilityCurrent Other current liabilities us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount Finance leases, Less imputed interest Market Price Risk Adjustment [Member] Relating to market price risk adjustment. Concentration Risk Type [Axis] 2027, finance leases belfa_RedeemableNoncontrollingInterestMeasurementInput Redeemable Noncontrolling Interest, Measurement Input Value of input used to measure redeemable noncontrolling interest. 2029, finance leases Forward Rate [Member] Relating to forward rate. 2028, finance leases Interest on lease liabilities - finance leases Operating cash flows from finance leases % by Which Estimated Fair Value Exceeds Carrying Value us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount Operating leases, Less imputed interest Operating lease liability, long-term Operating lease liability, long-term us-gaap_OperatingLeaseLiability Total operating lease liabilities Operating leases, Present value of lease liabilities Product Returns [Policy Text Block] Disclosure of accounting policy for product returns. Operating lease liability, current Operating lease liability, current Less: Net earnings attributable to noncontrolling interest Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Concentration Risk Type [Domain] us-gaap_LongTermDebtPercentageBearingFixedInterestRate Long-Term Debt, Percentage Bearing Fixed Interest, Percentage Rate SWITZERLAND us-gaap_LongTermDebtPercentageBearingVariableInterestRate Long-Term Debt, Percentage Bearing Variable Interest, Percentage Rate Business Combination, Contingent Consideration, Type [Domain] us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo 2027 Goodwill [Text Block] Long-term debt Business Combination, Contingent Consideration, Type [Axis] us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree 2028 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths 2026 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis Debt Securities, Available-for-Sale, Amortized Cost CHINA Standard Product Warranty, Policy [Policy Text Block] us-gaap_LongTermDebt Total long-term debt GERMANY Statement of Stockholders' Equity [Abstract] Finance Lease, Liability, Current, Statement of Financial Position Finance Lease, Liability, Noncurrent, Statement of Financial Position Statement of Comprehensive Income [Abstract] Cinch Connectivity Solutions [Member] Represents Cinch Connectivity Solutions. Statement of Cash Flows [Abstract] UNITED KINGDOM Shareholders' equity: us-gaap_LossContingencyEstimateOfPossibleLoss Loss Contingency, Estimate of Possible Loss Equity Components [Axis] Equity Component [Domain] Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] Equity [Text Block] AOCI Attributable to Parent [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Cost of sales ISRAEL INDIA Defined Benefit Plan, Plan with Projected Benefit Obligation in Excess of Plan Assets [Table Text Block] Machinery and Equipment [Member] Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Held to maturity U.S. Treasury securities Defined Benefit Plan, Assumptions [Table Text Block] Schedule of Net Benefit Costs [Table Text Block] Schedule of Expected Benefit Payments [Table Text Block] Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] MACAO The 2021 Swaps One [Member] The first of the 2021 interest rate swaps. The 2021 Swaps Two [Member] The second of the 2021 interest rate swaps. Foreign currency translation adjustment, net of taxes of ($312) at December 31, 2025 and ($312) at December 31, 2024 us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax The 2021 Swaps [Member] The aggregate two 2021 interest rate swap agreements entered in November 2021. Summary of Valuation Allowance [Table Text Block] Sales Channel, Through Intermediary [Member] Supplemental cash flow information: us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent Other foreign jurisdictions, percent Liabilities, Current [Abstract] us-gaap_CurrentIncomeTaxExpenseBenefit Current us-gaap_LiabilitiesCurrent Total current liabilities Derivatives Not Designated as Hedging Instruments [Table Text Block] Federal, current Foreign, current State, current Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue [Table Text Block] us-gaap_LongTermDebtFairValue Long-Term Debt, Fair Value us-gaap_TaxCreditCarryforwardAmount Tax Credit Carryforward, Amount Customer Concentration Risk [Member] us-gaap_HeldToMaturitySecurities Held to maturity U.S. Treasury securities, amortized cost Lease, Cost [Table Text Block] Derivative Instruments and Hedging Activities Disclosures [Table] Supplemental Employee Retirement Plan [Member] Customer Relationships [Member] Other Commitments [Table] SLOVAKIA Forfeiture of restricted common stock, APIC Intangible Assets Excluding Trademarks [Member] Represents intangible assets excluding trademarks. Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Long-Lived Asset [Table Text Block] Debt Disclosure [Text Block] Use of Estimates, Policy [Policy Text Block] Other Assets Disclosure [Text Block] Issuance of restricted common stock Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Lessee, Operating Leases [Text Block] us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners Subsidiary, Ownership Percentage, Noncontrolling Owner us-gaap_LineOfCreditFacilityCommitmentFeePercentage Line of Credit Facility, Commitment Fee Percentage UNITED STATES us-gaap_MinorityInterestOwnershipPercentageByParent Subsidiary, Ownership Percentage, Parent us-gaap_DebtInstrumentCarryingAmount Long-Term Debt, Gross Current assets: us-gaap_DebtWeightedAverageInterestRate Debt, Weighted Average Interest Rate Money Market Funds [Member] us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures Forfeiture of 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us-gaap_PaymentsOfDebtIssuanceCosts Deferred financing costs Intangible Asset, Finite-Lived, and Capitalized Cost, Software to be Sold, Leased, or Marketed, Estimated Amortization Expense [Table Text Block] us-gaap_NetCashProvidedByUsedInFinancingActivities Net cash (used in) provided by financing activities Finished goods Reporting Unit [Domain] Liability for uncertain tax positions Reporting Unit [Axis] Restructuring Type [Axis] belfa_PolicyTable Developed Technology Rights [Member] Accounting Policies [Abstract] us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense Deferred Compensation Arrangement with Individual, Compensation Expense us-gaap_DeferredCompensationPlanAssets Deferred Compensation Plan Assets us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted Purchase Commitment, Remaining Minimum Amount Committed US Treasury Securities [Member] Segments [Axis] Foreign, deferred Measurement Input Type [Axis] Federal, deferred us-gaap_UnrecognizedTaxBenefits 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Fair Value Hierarchy and NAV [Domain] Measurement Frequency [Domain] Nonqualified Deferred Compensation Plan [Member] Represents Nonqualified Deferred Compensation Plan. belfa_DeferredCompensationArrangementVestingAge Deferred Compensation Arrangement, Vesting Age The age of employees for contributions to become fully vested under deferred compensation arrangement. us-gaap_RepaymentsOfLinesOfCredit Repayments under revolving line of credit Statement of Financial Position [Abstract] us-gaap_IncomeTaxReconciliationTaxExemptIncome Nontaxable controlled foreign corporation ("CFC") income, amount Income taxes, net of refunds received Total income taxes paid Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Assets, Total [Member] Fair Value, Nonrecurring [Member] Other Assets, Noncurrent belfa_LongtermDebtGrossCurrentMaturities Less: Current maturities of long-term debt Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current.. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. us-gaap_PaymentsForRepurchaseOfCommonStock Purchase of treasury stock us-gaap_ConcentrationRiskPercentage1 Concentration Risk, Percentage belfa_LongtermDebtGrossNoncurrent Noncurrent portion of long-term debt Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Restructuring (credits) charges Actuarial loss (gain) us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) Foreign income tax paid Weighted-average shares outstanding: Net earnings per common share: Intangible Asset, Indefinite-Lived, Class [Domain] us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic Earnings per common share - basic and diluted (in dollars per share) us-gaap_TreasuryStockRetiredCostMethodAmount Cancellation of treasury shares Net earnings per common share, basic (in dollars per share) Net earnings per share, basic (in dollars per share) Research and Development Expense, Policy [Policy Text Block] Intangible Asset, Indefinite-Lived, Class [Axis] Effective Income Tax Rate Reconciliation [Table] State and Local Earnings Per Share, Policy [Policy Text Block] Federal Intangible assets, net belfa_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsGrantDateClosingPrice Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Grant Date Closing Price (in dollars per share) The grant date closing price used in the valuation of awards. Goodwill allocation related to acquisition Goodwill, Acquired During Period us-gaap_FiniteLivedIntangibleAssetsNet Net carrying amount Gross carrying amount Accrued restructuring costs us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill Trademarks us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts Business Acquisition, Transaction Costs Goodwill, net Goodwill Goodwill, net Goodwill, net Other liabilities Variable lease cost (cost excluded from lease payments) Power Solutions and Protection [Member] Represents the Power Solutions and Protection product group. Operating lease cost (cost resulting from lease payments) Short-term lease cost us-gaap_LeaseCost Total lease cost Business Combination [Domain] us-gaap_RevenueRemainingPerformanceObligation Revenue, Remaining Performance Obligation, Amount Business Combination [Axis] Investments Held in Rabbi Trust [Member] Information pertaining to investments held in a rabbi trust which are intended to fund the Company's Supplemental Executive Retirement Plan ("SERP"). belfa_AdjustmentsToAdditionalPaidInCapitalPurchaseOfTreasuryStock Purchase of common stock, APIC The amount of additional paid in capital for the purchase of treasury stock. Bel Fuse Inc. Employees' Savings Plan [Member] Information pertaining to the Bel Fuse Inc. Employees' Savings Plan. Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table] belfa_IncomeTaxExpenseBenefitOnReversalOfInterestAndPenalties Income Tax Expense (Benefit) on Reversal of Interest and Penalties The amount of current income tax expense (benefit) and deferred income tax expense (benefit) recognized on reversal of interest and penalties pertaining to continuing operations. us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired Business Acquisition, Percentage of Voting Interests Acquired Credit and Security Agreement with KeyBank [Member] Information pertaining to the Credit and Security Agreement with KeyBank National Association (as amended, the "CSA"). belfa_RestructuringCashPaymentsAndOtherSettlements Cash payment and other settlements The amount of cash payments made as the result of exit or disposal activities and any other settlements which is not reported separately during the period. Foreign currency translation adjustment, net of taxes us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax Currency translation adjustment, net of taxes of $0, $36 and ($93) Business Combination [Table] Retirement Fund Covering Hong Kong-based Employees [Member] Information pertaining to the Company's retirement fund which covers substantially all of their Hong Kong-based full-time employees. belfa_SharesHeldInPlan Shares Held in Plan (in shares) The number of shares of the company's common stock owned by the plan. Business Combination, Pro Forma Information [Table Text Block] Fair Value Measurement, Policy [Policy Text Block] Contract with Customer, Sales Channel [Domain] Arezzo Revenue Agency [Member] Information pertaining to Arezzo Revenue Agency. Contract with Customer, Sales Channel [Axis] belfa_NumberOfIndustryInWhichEntityOperates Number of Industry in which Entity Operates Number of industry in which entity operates with its reportable operating segments. Capital Addition Purchase Commitments [Member] Foreign currency translation adjustment, tax expense Foreign currency translation adjustment, tax expense Lessee, Operating and Financing Lease Liability Maturity [Table Text Block] Tabular disclosure of undiscounted cash flows of lessee's operating and financing lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to operating lease liability recognized in statement of financial position. Foreign currency translation adjustment, tax belfa_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax Represents the tax expense (benefit) arising from the accumulated appreciation or loss in value of foreign currency translation adjustment at the end of an accounting period. belfa_AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax Change in unfunded SERP liabilityChange in unfunded SERP liability, tax, tax Represents the tax portion in relation to net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other post-retirement plan(s) because they have yet to be recognized as components of net periodic benefit cost. Unrealized holding gains on available-for-sale securities, tax Represents the tax expense (benefit) of arising from the accumulated appreciation or loss in value of total available-for-sale securities at the end of an accounting period. us-gaap_InterestExpenseDebt Interest Expense, Debt Schedule of Changes in Accumulated Other Comprehensive Income (Loss) by Component [Table Text Block] Tabular disclosure of changes in components of accumulated other comprehensive income (loss). Interest expense Interest expense belfa_OperatingAndFinanceLeasesRemainingLeaseTerm Operating and Finance Leases, Remaining Lease Term (Year) The remaining lease term for operating and finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Acquisition resulting in redeemable noncontrolling interest ("NCI") Retained earnings Unbilled receivables Contract assets - current (unbilled receivables) Lease, Supplemental Balance Sheet Information [Table Text Block] Tabular disclosure of supplemental balance sheet information related to leases. Leases, Supplemental Cash Flow Information [Table Text Block] Tabular disclosure of supplemental cash flow information related to leases. Revenue from Contract with Customer [Text Block] us-gaap_IncreaseDecreaseInRestructuringReserve Accrued restructuring costs Assets under Finance Lease [Member] Information pertaining to assets under finance lease. Class of Stock [Axis] Deferred income taxes benefit/(expense) us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid Benefits paid us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid Benefits paid Derivative Instruments, Gain (Loss) [Table Text Block] Property, Plant, and Equipment [Table] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share (in dollars per share) Derivative Contract [Domain] Long-Lived Asset, Class [Axis] Cash and Cash Equivalents, Policy [Policy Text Block] Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Cash and cash equivalents Impaired Assets to be Disposed of by Method Other than Sale by Type [Axis] Cash [Member] us-gaap_CashFlowHedgeDerivativeInstrumentLiabilitiesAtFairValue Designated as cash flow hedges us-gaap_CashFlowHedgeDerivativeInstrumentAssetsAtFairValue Designated as cash flow hedges Investment [Text Block] belfa_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses Accrued expenses Amount of accrued expenses assumed at the acquisition date. us-gaap_ContractWithCustomerLiability Balance, January 1 Balance, December 31 Sellers Note [Member] Related to sellers note. Redemption value adjustment attributable to noncontrolling interest The value of redemption value adjustment attributable to noncontrolling interest. us-gaap_ContractWithCustomerLiabilityCurrent Contract liabilities - current (deferred revenue) us-gaap_PaymentsToAcquireBusinessesGross Cash paid Unfunded pension liability belfa_DeferredTaxLiabilitiesUnfundedPensionLiability Amount of deferred tax consequences attributable to taxable temporary differences derived from unfunded pension liability. belfa_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentInventoryNetOfTax Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory, Net of Tax This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to inventory acquired in connection with a business combination for which the initial accounting was incomplete, net of tax Common Stock Outstanding [Member] Represents common stock outstanding. Asset Class [Domain] belfa_TotalFinanceLeaseLiability Total finance lease liabilities The value of total finance lease liability. belfa_RedemptionValueAdjustmentOnRedeemableNoncontrollingInterest Redemption value adjustment on redeemable NCI The redemption value adjustment on redeemable noncontrolling interest. Interest payments Interest Rate Swap [Member] Inventory Disclosure [Text Block] Business Combination [Table Text Block] Enercon Technologies, Ltd [Member] In reference to Enercon Technologies, Ltd. Inventories Inventories us-gaap_StockholdersEquity Total shareholders' equity Balance Balance Goodwill [Table Text Block] SEC Schedule, 12-09, Allowance, Credit Loss [Member] Foreign Exchange Forward [Member] Right-of-use assets Operating lease right-of-use assets Property, Plant, and Equipment [Table Text Block] Net sales Depreciation us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment Inventory, Policy [Policy Text Block] us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance Change in valuation allowance, amount Document, Type Document, Period End Date Entity, Incorporation, State or Country Code Entity, File Number Entity, Tax Identification Number Entity, Address, Address Line One Entity, Address, City or Town Entity, Address, State or Province Entity, Address, Postal Zip Code City Area Code Local Phone Number Written Communications Soliciting Material Pre-commencement Tender Offer Pre-commencement Issuer Tender Offer Title of 12(b) Security Trading Symbol Security Exchange Name Entity, Emerging Growth Company ClassACommonStock010ParValue Custom [Member] ClassBCommonStock010ParValue Custom [Member]