Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2020	May 07, 2020
Document And Entity Information
Title of 12(b) Security	Common Stock, Par Value $2.50 per share
Entity Address, Address Line One	300 North Main Street
Entity Incorporation, State or Country Code	WV
Entity Interactive Data Current	Yes
Entity Registrant Name	Summit Financial Group, Inc.
City Area Code	304
Local Phone Number	530-1000
Entity Central Index Key	0000811808
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	0-16587
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		12,972,022
Entity Current Reporting Status	Yes
Entity Tax Identification Number	55-0672148
Entity Address, City or Town	Moorefield
Entity Address, State or Province	WV
Entity Address, Postal Zip Code	26836
Trading Symbol	SMMF
Security Exchange Name	NASDAQ