Cover Page - shares shares in Millions	6 Months Ended
	Jun. 30, 2019	Jul. 31, 2019
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
Document Transition Report	false
Entity File Number	1-12254
Entity Registrant Name	SAUL CENTERS INC.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	52-1833074
Entity Address, Address Line One	7501 Wisconsin Avenue
Entity Address, City or Town	Bethesda
Entity Address, State or Province	MD
Entity Address, Postal Zip Code	20814
City Area Code	301
Local Phone Number	986-6200
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		23.0
Entity Central Index Key	0000907254
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Common Stock
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value
Security Exchange Name	NYSE
Trading Symbol	BFS
6.875% Series C Preferred Stock, $0.01 par value
Entity Information [Line Items]
Title of 12(b) Security	6.875% Series C Preferred Stock, $0.01 par value
Security Exchange Name	NYSE
Trading Symbol	BFS/PRC
6.125% Series D Preferred Stock, $0.01 par value
Entity Information [Line Items]
Title of 12(b) Security	6.125% Series D Preferred Stock, $0.01 par value
Security Exchange Name	NYSE
Trading Symbol	BFS/PRD