Information pertaining to the debt covenant.

No definition available.

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Namespace Prefix:	bkti_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Information pertaining to the debt covenant.

+ References

No definition available.

+ Details

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Namespace Prefix:	bkti_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of interest expense and related servicing fees attached to a debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	bkti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of required periodic payments including both interest and principal payments.

+ References

No definition available.

+ Details

Name:	bkti_DebtInstrumentNumberOfPaymentsForPrincipalAndInterest
Namespace Prefix:	bkti_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The gain or loss associated with the exchange of short-term trade receivables.

+ References

No definition available.

+ Details

Name:	bkti_GainlossOnExchangeOfShorttermTradeReceivables
Namespace Prefix:	bkti_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum percentage of eligible accounts receivable for borrowing capacity of the line of credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	bkti_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum percentage of net orderly liquidation value of inventory for borrowing capacity of the line of credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	bkti_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Expansion on the maximum amount allowed on a line of credit.

+ References

No definition available.

+ Details

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Namespace Prefix:	bkti_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	bkti_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from exchange of short-term trade receivables.

+ References

No definition available.

+ Details

Name:	bkti_ProceedsFromExchangeOfShorttermTradeReceivables
Namespace Prefix:	bkti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of value of transferred receivables to be received in cash.

+ References

No definition available.

+ Details

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Namespace Prefix:	bkti_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
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-Subparagraph (b)
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

+ Details

Name:	us-gaap_DebtInstrumentPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Indicates type of variable interest rate on debt instrument.

+ References

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-Topic 942
-SubTopic 470
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-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
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Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 1A
-Subparagraph (b)(1)
-SubTopic 30
-Topic 860
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-URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=bkti_AlternaCapitalSolutionsLlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_AccountsReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=bkti_InvoicePurchaseAndSecurityAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=bkti_JpMorganChaseBankNaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_NotesPayableToBanksMember
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Data Type:	na
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Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=bkti_UsBankEquipmentFinanceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Data Type:	na
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- Details

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Note 6 - Debt (Details Textual) $ in Thousands					9 Months Ended	12 Months Ended
Note 6 - Debt (Details Textual) $ in Thousands	Oct. 30, 2024 USD ($)	Nov. 22, 2023	Nov. 22, 2022 USD ($)	Sep. 25, 2019 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Apr. 06, 2021 USD ($)
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]		Prime Rate [Member]
Alterna Capital Solutions, LLC [Member] \| Accounts Receivable [Member]
Gain/(Loss) on Exchange of Short-Term Trade Receivables					$ 0		$ 0
Alterna Capital Solutions, LLC [Member] \| Invoice Purchase and Security Agreement [Member]
Line of Credit Facility, Expiration Period (Year)		1 year	1 year
Line of Credit Facility, Maximum Borrowing Capacity			$ 15,000
Line of Credit Facility, Borrowing Capacity, Percentage of Net Orderly Liquidation Value			75.00%
Line of Credit Facility, Borrowing Capacity, Maximum Percentage of Eligible Account Balances			100.00%
Debt Instrument, Interest Rate, Stated Percentage			1.85%
Debt Instrument, Interest Expense and Related Servicing Fees						$ 356	648
Transferred Short-Term Trade Receivable to Cash, Percentage			85.00%
Transfers Accounted for as Secured Borrowings, Assets, Carrying Amount						49,700	67,400
Proceeds from Exchange of Short-Term Trade Receivables						46,400	$ 74,600
JP Morgan Chase Bank, N.A. [Member] \| Notes Payable to Banks [Member]
Debt Instrument, Face Amount								$ 743
U.S. Bank Equipment Finance [Member] \| Notes Payable to Banks [Member]
Debt Instrument, Interest Rate, Stated Percentage				5.11%
Debt Instrument, Face Amount				$ 425
Debt Instrument, Number of Payments for Principal and Interest				60
Debt Instrument, Periodic Payment				$ 8
Revolving Credit Facility [Member] \| Fifth Third Credit Agreement [Member]
Line of Credit Facility, Expiration Period (Year)	1 year
Line of Credit Facility, Maximum Borrowing Capacity	$ 6,000
Line of Credit Facility, Maximum Borrowing Capacity, Accordion Feature	4,000
Line of Credit Facility, Maximum Borrowing Capacity, Including Accordion Feature, Total	$ 10,000
Debt Instrument, Basis Spread on Variable Rate	2.50%
Debt Instrument, Covenant, Total Funded Debt Ratio	2
Debt Instrument, Covenant, Fixed Charge Ratio	1.2
Long-Term Line of Credit						$ 0