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Consolidated Statements of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Series A Preferred Stock	Series B Preferred Stock	Series C Preferred Stock	Preferred Stock	Preferred Stock Series A Preferred Stock	Preferred Stock Series B Preferred Stock	Preferred Stock Series C Preferred Stock	Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Series A Preferred Stock	Additional Paid-in Capital Series B Preferred Stock	Additional Paid-in Capital Series C Preferred Stock	Accumulated Deficit	Accumulated Deficit Series A Preferred Stock	Accumulated Deficit Series B Preferred Stock	Accumulated Other Comprehensive (Loss)	Total Saul Centers, Inc.	Total Saul Centers, Inc. Series A Preferred Stock	Total Saul Centers, Inc. Series B Preferred Stock	Total Saul Centers, Inc. Series C Preferred Stock	Noncontrolling Interest	Dividend Paid	Dividend Paid Series A Preferred Stock	Dividend Paid Series B Preferred Stock	Dividend Paid Series C Preferred Stock	Dividend Paid Accumulated Deficit	Dividend Paid Accumulated Deficit Series A Preferred Stock	Dividend Paid Accumulated Deficit Series B Preferred Stock	Dividend Paid Accumulated Deficit Series C Preferred Stock	Dividend Paid Total Saul Centers, Inc.	Dividend Paid Total Saul Centers, Inc. Series A Preferred Stock	Dividend Paid Total Saul Centers, Inc. Series B Preferred Stock	Dividend Paid Total Saul Centers, Inc. Series C Preferred Stock	Dividend Paid Noncontrolling Interest	Dividend Declared	Dividend Declared Series A Preferred Stock	Dividend Declared Series B Preferred Stock	Dividend Declared Accumulated Deficit	Dividend Declared Accumulated Deficit Series A Preferred Stock	Dividend Declared Accumulated Deficit Series B Preferred Stock	Dividend Declared Total Saul Centers, Inc.	Dividend Declared Total Saul Centers, Inc. Series A Preferred Stock	Dividend Declared Total Saul Centers, Inc. Series B Preferred Stock	Dividend Declared Noncontrolling Interest
Beginning Balance at Dec. 31, 2011	$ 293,206				$ 179,328				$ 193	$ 217,829				$ (144,659)			$ (2,863)	$ 249,828				$ 43,378
Issuance of common stock:
Pursuant to dividend reinvestment plan	23,130								6	23,124								23,130
Exercise of employee stock options and issuance of directors' deferred stock	5,606								2	5,604								5,606
Net income	39,780us-gaap_ProfitLoss													33,374				33,374				6,406
Change in unrealized loss on cash flow hedge	(932)																(690)	(690)				(242)
Preferred stock distributions:
Preferred stock distributions																								(6,000)	(5,355)			(6,000)	(5,355)			(6,000)	(5,355)				(2,000)	(1,785)		(2,000)	(1,785)		(2,000)	(1,785)
Common stock distributions																							(28,656)				(21,189)				(21,189)				(7,467)
Distributions payable preferred stock
Distributions payable common stock and distributions payable partnership units																																				(9,705)			(7,216)			(7,216)			(2,489)
Ending Balance at Dec. 31, 2012	307,289				179,328				201	246,557				(154,830)			(3,553)	267,703				39,586
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares of Series C preferred stock				135,193				140,000					(4,807)								135,193
Redemption of preferred stock		(60,004)	(79,333)			(60,000)	(79,328)				2,212	3,007			(2,216)	(3,012)			(60,004)	(79,333)
Issuance of common stock:
Pursuant to dividend reinvestment plan	20,672								5	20,667								20,672
Exercise of employee stock options and issuance of directors' deferred stock	2,792									2,792								2,792
Issuance of partnership units pursuant to dividend reinvestment plan	4,144																					4,144
Net income	34,842us-gaap_ProfitLoss													30,872				30,872				3,970
Change in unrealized loss on cash flow hedge	2,897																2,161	2,161				736
Preferred stock distributions:
Preferred stock distributions																								(3,213)	(1,468)	(6,095)		(3,213)	(1,468)	(6,095)		(3,213)	(1,468)	(6,095)			(800)	(2,406)		(800)	(2,406)		(800)	(2,406)
Common stock distributions																							(29,455)				(21,988)				(21,988)				(7,467)
Distributions payable preferred stock
Distributions payable common stock and distributions payable partnership units																																				(9,929)			(7,408)			(7,408)			(2,521)
Ending Balance at Dec. 31, 2013	315,126				180,000				206	270,428				(172,564)			(1,392)	276,678				38,448
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares of Series C preferred stock				39,260				40,000					(740)								39,260
Redemption of preferred stock		(40,000)				(40,000)					1,475				(1,475)				(40,000)
Issuance of common stock:
Pursuant to dividend reinvestment plan	9,264								2	9,262								9,264
Exercise of employee stock options and issuance of directors' deferred stock	7,571								1	7,570								7,571
Issuance of partnership units pursuant to dividend reinvestment plan	8,877																					8,877
Net income	57,988us-gaap_ProfitLoss													46,943				46,943				11,045
Change in unrealized loss on cash flow hedge	(675)																(502)	(502)				(173)
Preferred stock distributions:
Preferred stock distributions																								(3,049)		(7,219)		(3,049)		(7,219)		(3,049)		(7,219)				(3,094)			(3,094)			(3,094)
Common stock distributions																							(33,534)				(24,937)				(24,937)				(8,597)
Distributions payable preferred stock
Distributions payable common stock and distributions payable partnership units																																				(11,258)			(8,379)			(8,379)			(2,879)
Ending Balance at Dec. 31, 2014	$ 339,257				$ 180,000				$ 209	$ 287,995				$ (173,774)			$ (1,894)	$ 292,536				$ 46,721