Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 07, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	CHEMUNG FINANCIAL CORP
Entity Central Index Key	0000763563
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Document Type	10-Q
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		4,842,971