Debt Instrument, Interest Rate Term

No definition available.

Name:	bcbp_DebtInstrumentInterestRateTerm
Namespace Prefix:	bcbp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Remaining Amount

+ References

No definition available.

+ Details

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Namespace Prefix:	bcbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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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+ Details

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

- Definition

The average effective interest rate during the reporting period.

+ References

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+ Details

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

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, 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_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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+ Details

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

- Definition

The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

+ References

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+ Details

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

- Definition

Amount that would be paid, determined under the conditions specified in the contract, if the holder of the share has the right to redeem the shares.

+ References

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+ Details

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

- Definition

Stated interest rate of the subordinated debt.

+ 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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Balance Type:
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- Details

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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubordinatedBorrowingAxis=bcbp_TrustPreferredJuniorSubordinatedDebentureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subordinated Debt (Narrative) (Details) - USD ($)			9 Months Ended
Subordinated Debt (Narrative) (Details) - USD ($)	Aug. 29, 2024	Aug. 01, 2023	Sep. 30, 2024	Nov. 01, 2024	Dec. 31, 2023	Jul. 30, 2018
Subordinated Borrowing [Line Items]
Face amount						$ 33,500,000
Proceeds from Issuance of Subordinated Long-term Debt			$ 38,799,000
Repurchase Amount			$ 9,400,000
Fixed To Floating Rate Subordinated Debentures [Member]
Subordinated Borrowing [Line Items]
Face amount	$ 40,000,000
Notes term	10 years	5 years	10 years
Debt Instrument, Interest Rate During Period			8.22929%
Variable interest rate spread			0.26161%
Deferred finance costs					$ 116,000
Fixed To Floating Rate Subordinated Debentures [Member] \| Forecast [Member]
Subordinated Borrowing [Line Items]
Remaining Amount				$ 24,100,000
Fixed To Floating Rate Subordinated Debentures [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Subordinated Borrowing [Line Items]
Variable interest rate spread	5.82%
Fixed To Floating Rate Subordinated Debentures [Member] \| First Five Years [Member]
Subordinated Borrowing [Line Items]
Notes term	5 years
Interest rate	9.25%		5.625%
Interest rate term			5 years
Fixed To Floating Rate Subordinated Debentures [Member] \| After Five Years [Member]
Subordinated Borrowing [Line Items]
Variable interest rate spread		2.72%
Trust Preferred Junior Subordinated Debenture [Member]
Subordinated Borrowing [Line Items]
Debt Instrument, Interest Rate During Period			7.85279%
Variable interest rate spread			2.65%
Trust preferred securities			$ 4,100,000