Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2022	Aug. 02, 2022
Document And Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2022
Document Transition Report	false
Entity File Number	0-50275
Entity Registrant Name	BCB Bancorp, Inc.
Entity Incorporation, State or Country Code	NJ
Entity Tax Identification Number	26-0065262
Entity Address, Address Line One	104-110 Avenue C
Entity Address, City or Town	Bayonne
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07002
City Area Code	201
Local Phone Number	823-0700
Title of 12(b) Security	Common Stock, no par value
Security Exchange Name	NASDAQ
Trading Symbol	BCBP
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		16,981,867
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001228454
Amendment Flag	false