Document And Entity Information	3 Months Ended
	Jun. 30, 2013	Aug. 01, 2013
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2013
Document Period End Date	Jun. 30, 2013
Current Fiscal Year End Date	--12-31
Entity Registrant Name	CommunityOne Bancorp
Entity Central Index Key	0000764811
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		21,736,873