Document and Entity Information (USD $)	3 Months Ended
	Mar. 31, 2013	Apr. 30, 2013	Nov. 01, 2012
Document and Entity Information [Abstract]
Entity Registrant Name	CITIZENS FINANCIAL SERVICES INC
Entity Central Index Key	0000739421
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float		$ 2,893,595
Entity Common Stock, Shares Outstanding			2,914,190
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2013