Document and Entity Information (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Mar. 01, 2013	Jun. 30, 2012
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2012
Entity Registrant Name	CENTER BANCORP INC
Document Fiscal Period Focus	FY
Entity Filer Category	Accelerated Filer
Entity Central Index Key	0000712771
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2012
Entity Common Stock, Shares Outstanding		16,348,915
Entity Current Reporting Status	Yes
Entity Public Float			$ 135.2
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No