Document And Entity Information (USD $)	9 Months Ended
	Sep. 30, 2012	Nov. 06, 2012	Jun. 30, 2012
Document and Entity Information [Abstract]
Entity Registrant Name	AMERICAN RIVER BANKSHARES
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		9,327,920
Entity Public Float			$ 62,573,000
Amendment Flag	false
Entity Central Index Key	0001108236
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Document Period End Date	Sep. 30, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q3