Regulatory Matters (Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations) (Details) - BCB Community Bank [Member] $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total capital (to risk-weighted assets): Actual - Amount		$ 278,229
Total capital (to risk-weighted assets): Actual - Ratio		0.0985
Total capital (to risk-weighted assets): For Capital Adequacy Purposes - Amount		$ 197,169
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		$ 225,336
Total capital (to risk-weighted assets): To be Well Capitalized under Prompt Corrective Action Provisions - Ratio		0.0800
Tier 1 capital (to average assets): Actual - Amount	$ 299,247
Tier 1 capital (to average assets): Actual - Ratio	0.0992
Tier 1 capital (to average assets): For Capital Adequacy Purposes - Amount	$ 211,177
Tier 1 capital (to average assets): For Capital Adequacy Purposes - Ratio	0.0700
Tier 1 capital (to average assets): To be Well Capitalized under Prompt Corrective Action Provisions - Amount	$ 256,429
Tier 1 capital (to average assets): To be Well Capitalized under Prompt Corrective Action Provisions - Ratio	0.0850

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
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 942
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-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

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

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