Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Nov. 02, 2018
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Entity Registrant Name	SAGA COMMUNICATIONS INC
Entity Central Index Key	0000886136
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Trading Symbol	SGA
Entity Emerging Growth Company	false
Entity Small Business	false
Common Class A [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		5,011,580
Common Class B [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		898,633