Regulatory Matters (Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations) (Details) $ in Thousands	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
BCB Community Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total capital (to risk-weighted assets): Actual - Amount	$ 363,697	$ 350,749
Total capital (to risk-weighted assets): Actual - Ratio	0.1003	0.0909
Total capital (to risk-weighted assets): For Capital Adequacy Purposes - Amount	$ 290,087	$ 308,608
Total capital (to risk-weighted assets): For Capital Adequacy Purposes - Ratio	0.0800	0.0800
Total capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Amount	$ 326,348	$ 347,184
Total capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Ratio	0.0900	0.0900
Bancorp [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total capital (to risk-weighted assets): Actual - Amount	$ 400,591	$ 379,562
Total capital (to risk-weighted assets): Actual - Ratio	0.1289	0.1114
Total capital (to risk-weighted assets): For Capital Adequacy Purposes - Amount	$ 248,621	$ 272,564
Total capital (to risk-weighted assets): For Capital Adequacy Purposes - Ratio	0.0800	0.0800
Total capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Amount	$ 310,777	$ 340,705
Total capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Ratio	0.1000	0.1000
Tier 1 capital (to risk-weighted assets): Actual - Amount	$ 326,965	$ 319,154
Tier 1 capital (to risk-weighted assets): Actual - Ratio	0.1052	0.0937
Tier 1 capital (to risk-weighted assets): For Capital Adequacy Purposes - Amount	$ 186,482	$ 204,422
Tier 1 capital (to risk-weighted assets): For Capital Adequacy Purposes - Ratio	0.0600	0.0600
Tier 1 capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Amount	$ 186,482	$ 204,422
Tier 1 capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Ratio	0.0600	0.0600
Common Equity Tier 1 (to risk-weighted assets): Actual - Amount	$ 298,118	$ 289,987
Common Equity Tier 1 (to risk-weighted assets): Actual - Ratio	0.0959	0.0851
Common Equity Tier 1 (to risk-weighted assets): For Capital Adequacy Purposes - Amount	$ 139,889	$ 153,317
Common Equity Tier 1 (to risk-weighted assets): For Capital Adequacy Purposes - Ratio	0.0450	0.0450
Tier 1 capital (to average assets): Actual - Amount	$ 326,965	$ 319,154
Tier 1 capital (to average assets): Actual - Ratio	0.0902	0.0827
Tier 1 capital (to average assets): For Capital Adequacy Purposes - Amount	$ 144,996	$ 154,315
Tier 1 capital (to average assets): For Capital Adequacy Purposes - Ratio	0.0400	0.0400

Common Equity Tier One

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Common Equity Tier One Required For Capital Adequacy

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Common Equity Tier One To Risk-Weighted Assets

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Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Section 50
-Paragraph 1B
-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

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