Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2016	Oct. 24, 2016
Document And Entity Information
Entity Registrant Name	MERCHANTS BANCSHARES INC
Trading Symbol	mbvt
Entity Central Index Key	0000726517
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		6,885,686
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q3