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Capitalized Product Development Costs Disclosure [Text Block] The entire disclosure relating to capitalized product development costs. Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Employee And Nonemployee Director [Member] Represents information pertaining to employee and nonemployee directors. Internal Revenue Service (IRS) [Member] Income Tax Jurisdiction [Axis] Income Tax Jurisdiction [Domain] Domestic Tax Jurisdiction [Member] Expired, Weighted Average Grant Date Fair Value per Share (in dollars per share) The weighted average grant-date fair value of options expired during the reporting period as calculated by applying the disclosed option pricing methodology. Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member] bkti_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageGrantDateFairValue Outstanding, Weighted Average Grant Date Fair Value per Share (in dollars per share) Outstanding, Weighted Average Grant Date Fair Value per Share (in dollars per share) Weighted average grant-date fair value of options outstanding. bkti_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionVestedWeightedAverageGrantDateFairValue Vested, Weighted Average Grant Date Fair Value per Share (in dollars per share) Vested, Weighted Average Grant Date Fair Value per Share (in dollars per share) Weighted average grant-date fair value of vested options outstanding. Document Annual Report Machinery and Equipment [Member] Cash and Cash Equivalents, Policy [Policy Text Block] Statement of Financial Position Location, Balance [Axis] Change in Unrecognized Tax Benefit, Reasonably Possible [Table] Nonvested, Aggregate Intrinsic Value Amount by which the current fair value of the underlying non-vested stock exceeds the exercise price of options that are non-vested. Statement of Financial Position Location, Balance [Domain] Entity Incorporation, State or Country Code us-gaap_UnrecognizedTaxBenefits Unrecognized Tax Benefits Unrecognized tax benefits as of January 1 Balance at December 31, us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Accounting Policies [Abstract] us-gaap_OpenTaxYear Open Tax Year Document Transition Report Document Financial Statement Error Correction [Flag] United States Government Agencies [Member] Represents information pertaining to the United States government agencies. Decreases related to lapses of statute of limitations Concentration Risk Disclosure [Text Block] us-gaap_ShortTermBorrowings Short-Term Debt Schedules of Concentration of Risk, by Risk Factor [Table Text Block] Entity Interactive Data Current us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease Unrecognized Tax Benefits, Period Increase (Decrease) Concentration Risk [Table] Decreases related to settlements of prior year tax positions Document Financial Statement Restatement Recovery Analysis [Flag] Security Exchange Name Increases related to current year tax positions Title of 12(b) Security us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs Uncollectible accounts written off bkti_EffectiveIncomeTaxRateReconciliationDeferredResearchAndExperimentalCostsAmount Deferred only - Section 174, amount Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deferred research and experimental costs. Deferred only - Stock based compensation, amount Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deferred stock based compensation. Deferred only - Stock based compensation, percent Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deferred stock based compensation. bkti_EffectiveIncomeTaxRateReconciliationChangeinUnrecognizedTaxBenefitsPercent Changes in unrecognized tax benefits Amount of percentage increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns. bkti_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits Changes in unrecognized tax benefits, amount Represents the amount of change in unrecognized tax benefits under an effective income tax rate reconciliation. Accounts and Financing Receivables [Table] Deferred only - Section 174, percent Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other deferred research and experimental costs. Auditor Name bkti_LineOfCreditFacilityBorrowingCapacityPercentageOfNetOrderlyLiquidationValue Line of Credit Facility, Borrowing Capacity, Percentage of Net Orderly Liquidation Value Maximum percentage of net orderly liquidation value of inventory for borrowing capacity of the line of credit facility. New Mexico Tax [Member] Represents New Mexico tax. Florida Tax [Member] Represents Florida tax. bkti_TransferredShorttermTradeReceivableToCashPercentage Transferred Short-Term Trade Receivable to Cash, Percentage Percentage of value of transferred receivables to be received in cash. Oregon Tax [Member] Represents Oregon tax. bkti_DebtInstrumentInterestExpenseAndRelatedServicingFees Debt Instrument, Interest Expense and Related Servicing Fees Amount of interest expense and related servicing fees attached to a debt instrument. Auditor Firm ID Schedule of Cash Paid for Income Taxes [Table Text Block] Represents the tabular disclosure of cash paid for income taxes during the period. Auditor Location Lease Liability The amount of deferred tax assets related to lease liabilities. bkti_LesseeOperatingLeaseAnnualRentalMaintenanceAndTaxExpense Lessee, Operating Lease, Annual Rental, Maintenance, and Tax Expense Amount of annual rental, maintenance, and tax expenses attributable to operating leases. Other States Tax [Member] Represents other states tax. Idaho Tax [Member] Represents Idaho tax. us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) Weighted average shares outstanding-diluted (in shares) Denominator for diluted earnings per share weighted average shares (in shares) Office Space at Sawgrass Technology Park [Member] Represents information pertaining to office space at Sawgrass Technology Park. Industrial Space in West Melbourne, Florida [Member] Represents information pertaining to the lease for industrial space in West Melbourne, Florida. us-gaap_PurchaseObligation Purchase Obligation Seven Suppliers [Member] Represents seven suppliers. Non-US [Member] The 2023 Executive Salary Swap Plan [Member] Represents the 2023 executive salary swap plan. Statement [Table] The 2024 Executive Salary Swap Plan [Member] Represents the 2024 executive salary swap plan. Statement of Financial Position [Abstract] Net income per share-diluted (in dollars per share) Diluted earnings per share (in dollars per share) Uncertain tax position Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to uncertain tax positions. Weighted average shares outstanding-basic (in shares) bkti_PreferredStockTotalReturnMultiplierofPositiveProfits Stock Issued During Period, Periodic Return on Investment, Percentage The total return on preferred stock as a multiplier of positive profits. us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments Other, percent bkti_ProceedsFromExchangeOfShorttermTradeReceivables Proceeds from Exchange of Short-Term Trade Receivables The cash inflow from exchange of short-term trade receivables. FG Holdings LLC. [Member] Represents information pertaining to FG holdings LLC. us-gaap_EffectiveIncomeTaxRateContinuingOperations Effective tax rate, percent Net income per share-basic (in dollars per share) Basic earnings per share (in dollars per share) Impact from rate changes Credit Loss, Financial Instrument [Policy Text Block] Change in valuation allowance U.S. Bank Equipment Finance [Member] Represents information pertaining to the U.S Bank Equipment Finance division. Statement of Cash Flows [Abstract] Invoice Purchase and Security Agreement [Member] Represents information pertaining to invoice purchase and security agreements. bkti_GainlossOnExchangeOfShorttermTradeReceivables Gain/(Loss) on Exchange of Short-Term Trade Receivables The gain or loss associated with the exchange of short-term trade receivables. Lease Contractual Term [Domain] Statement of Stockholders' Equity [Abstract] Lease Contractual Term [Axis] bkti_DebtInstrumentNumberOfPaymentsForPrincipalAndInterest Debt Instrument, Number of Payments for Principal and Interest The number of required periodic payments including both interest and principal payments. Income Statement [Abstract] Proceeds from credit facility and notes payable Amortization of deferred finance and other assets The amortization for deferred finance and other assets. us-gaap_RepaymentsOfDebt Repayment of credit facility and notes payable Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Issued, Weighted Average Remaining Contractual Life (Year) Weighted average remaining contractual term for vested portions of options issued during the period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Other nontaxable or nondeductible items, percent Expired, Aggregate Intrinsic Value Amount by which the current fair value of the underlying stock exceeds the exercise price of options expired during the period. Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Permanent differences Forfeited, Aggregate Intrinsic Value Amount by which the current fair value of the underlying stock exceeds the exercise price of options forfeited during the period. Share-based Compensation, percent Accounting Standards Update and Change in Accounting Principle [Table] Range Four [Member] Represents the fourth exercise price range. Range Three [Member] Represents the third exercise price range. Fifth Third Credit Agreement [Member] Information pertaining to the credit agreement. srt_StockRepurchaseProgramAuthorizedAmount1 Share Repurchase Program, Authorized, Amount State taxes, net of federal benefit State and local income taxes1, net of federal income tax effect, percent Other Commitments [Table] Options Exercisable, Upper Range Limit (in dollars per share) The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under exercisable stock option awards on all stock option plans and other required information pertaining to awards in the customized range. Options Exercisable, Lower Range Limit (in dollars per share) The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under exercisable stock option awards on all stock option plans and other required information pertaining to awards in the customized range. Other us-gaap_IncomeTaxReconciliationOtherAdjustments Financing activities U.S. federal statutory income tax rate, percent bkti_LineOfCreditFacilityBorrowingCapacityMaximumPercentageOfEligibleAccountBalances Line of Credit Facility, Borrowing Capacity, Maximum Percentage of Eligible Account Balances Maximum percentage of eligible accounts receivable for borrowing capacity of the line of credit facility. Lessee, Operating Lease, Supplemental Cash Flow Information [Table Text Block] The entire tabular disclosure for the supplemental cash flow information in regards to operating leases. bkti_PreferredStockTotalReturnPercentageOfPositiveProfits Preferred Stock, Total Return, Percentage of Positive Profits The total return on preferred stock as a percentage of positive profits. Series A Preferred Stock [Member] Series B Preferred Stock [Member] Research and development tax credits Represents the amount of research tax credits reported under an income tax reconciliation. us-gaap_StockholdersEquity Total stockholders’ equity Balance Balance Operating cash flows (liability reduction) Deferred revenue us-gaap_ContractWithCustomerLiabilityNoncurrent bkti_IncomeTaxReconciliationTaxCreditsResearchPercent Research and development tax credits Represents the percentage of research tax credits reported under an income tax reconciliation. Other nontaxable or nondeductible items, amount Common stock issued-warrants exercised (in shares) Number of warrants exercised during the current period. Common stock issued-warrants exercised Value of stock issued as a result of the exercise of warrants. Supplier [Axis] Class of Stock [Axis] Deferred Policy Acquisition Cost [Table] Supplier [Domain] Class of Stock [Domain] Share-based Compensation, amount Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Options Outstanding, Weighted Average Exercise Price (in dollars per share) Options Outstanding, Weighted Average Remaining Contractual Life (Year) Options Exercisable, Shares (in shares) Operating Segments [Member] Options Exercised, Weighted Average Exercise Price (in dollars per share) 11.51Options Outstanding, Upper Price Range (in dollars per share) Options Outstanding, Shares (in shares) State and local income taxes1, net of federal income tax effect, amount Exercise Price Range [Axis] Exercise Price Range [Domain] Options Outstanding, Lower Price Range (in dollars per share)