Regulatory Matters (Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations) (Details) - BCB Community Bank [Member] $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total capital (to risk-weighted assets): Actual - Amount		$ 299,247
Total capital (to risk-weighted assets): Actual - Ratio		0.0992
Total capital (to risk-weighted assets): For Capital Adequacy Purposes - Amount		$ 211,177
Total capital (to risk-weighted assets): For Capital Adequacy Purposes - Ratio		0.0700
Total capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Amount		$ 256,429
Total capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Ratio		0.0850
Tier 1 capital (to average assets): Actual - Amount	$ 327,806
Tier 1 capital (to average assets): Actual - Ratio	0.0986
Tier 1 capital (to average assets): For Capital Adequacy Purposes - Amount	$ 265,557
Tier 1 capital (to average assets): For Capital Adequacy Purposes - Ratio	0.0800
Tier 1 capital (to average assets): To be Well Capitalized under Prompt Corrective Action Provisions - Amount	$ 298,752
Tier 1 capital (to average assets): To be Well Capitalized under Prompt Corrective Action Provisions - Ratio	0.0900

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

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-Section 50
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Amount of Tier 1 leverage capital as defined by regulatory framework.

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