Document and Entity Information Document	6 Months Ended
	Jun. 30, 2012
Entity Information [Line Items]
Entity Registrant Name	Arrow Financial Corporation
Entity Central Index Key	0000717538
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding	11,767,145
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes