Saul Centers (BFS) 10-Q 4 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares shares in Millions	9 Months Ended
	Sep. 30, 2021	Oct. 31, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
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	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		23.7
Entity Central Index Key	0000907254
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Stock
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, Par Value $0.01 Per Share
Trading Symbol	BFS
Security Exchange Name	NYSE
Depositary Shares each representing 1/100th of a share of 6.125% Series D Cumulative Redeemable Preferred Stock, Par Value $0.01 Per Share
Entity Information [Line Items]
Title of 12(b) Security	Depositary Shares each representing 1/100th of a share of 6.125% Series D Cumulative Redeemable Preferred Stock, Par Value $0.01 Per Share
Trading Symbol	BFS/PRD
Security Exchange Name	NYSE
Depositary Shares each representing 1/100th of a share of 6.000% Series E Cumulative Redeemable Preferred Stock, Par Value $0.01 Per Share
Entity Information [Line Items]
Title of 12(b) Security	Depositary Shares each representing 1/100th of a share of 6.000% Series E Cumulative Redeemable Preferred Stock, Par Value $0.01 Per Share
Trading Symbol	BFS/PRE
Security Exchange Name	NYSE

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Real estate investments
Land	$ 511,596	$ 511,482
Buildings and equipment	1,563,059	1,543,837
Construction in progress	191,707	69,477
Total purchase price	2,266,362	2,124,796
Accumulated depreciation	(639,241)	(607,706)
Real estate investments, net	1,627,121	1,517,090
Cash and cash equivalents	11,917	26,856
Accounts receivable and accrued income, net	61,855	64,917
Deferred leasing costs, net	24,638	26,872
Other assets	13,969	9,837
Total assets	1,739,500	1,645,572
Liabilities
Notes payable	794,586	827,603
Construction loan payable	147,112	144,607
Revolving credit facility payable	95,028	103,913
Term loan facility payable	99,209	74,791
Accounts payable, accrued expenses and other liabilities	27,199	24,384
Deferred income	26,216	23,293
Dividends and distributions payable	20,543	19,448
Total liabilities	1,209,893	1,218,039
Equity
Common stock, $0.01 par value, 40,000,000 shares authorized, 23,713,961 and 23,476,626 shares issued and outstanding, respectively	237	235
Additional paid-in capital	430,537	420,625
Partnership units in escrow	79,300	0
Distributions in excess of accumulated earnings	(252,309)	(241,535)
Total Saul Centers, Inc. equity	442,765	364,325
Noncontrolling interests	86,842	63,208
Total equity	529,607	427,533
Total liabilities and equity	1,739,500	1,645,572
Series D Cumulative Redeemable Preferred Stock
Equity
Preferred stock, 1,000,000 shares authorized: Series D Cumulative Redeemable, 30,000 shares issued and outstanding, Series E Cumulative Redeemable, 44,000 shares issued and outstanding	75,000	75,000
Series E Cumulative Redeemable Preferred Stock
Equity
Preferred stock, 1,000,000 shares authorized: Series D Cumulative Redeemable, 30,000 shares issued and outstanding, Series E Cumulative Redeemable, 44,000 shares issued and outstanding	$ 110,000	$ 110,000

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Preferred stock, shares authorized	1,000,000	1,000,000
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	23,713,961	23,476,626
Common stock, shares outstanding	23,713,961	23,476,626
Series D Cumulative Redeemable Preferred Stock
Cumulative redeemable preferred stock, shares issued	30,000	30,000
Cumulative redeemable preferred stock, shares outstanding	30,000	30,000
Series E Cumulative Redeemable Preferred Stock
Cumulative redeemable preferred stock, shares issued	44,000	44,000
Cumulative redeemable preferred stock, shares outstanding	44,000	44,000

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue
Rental revenue	$ 59,058	$ 55,749	$ 175,634	$ 163,167
Other	1,198	1,011	3,351	3,756
Total revenue	60,256	56,760	178,985	166,923
Expenses
Property operating expenses	8,210	7,416	24,420	20,862
Real estate taxes	7,154	7,523	22,121	22,027
Interest expense, net and amortization of deferred debt costs	10,914	12,398	34,559	34,011
Depreciation and amortization of lease costs	12,467	13,713	37,852	37,593
General and administrative	4,626	4,107	14,234	13,790
Total expenses	43,371	45,157	133,186	128,283
Net Income	16,885	11,603	45,799	38,640
Noncontrolling interests
Income attributable to noncontrolling interests	(3,747)	(2,236)	(9,653)	(7,681)
Net income attributable to Saul Centers, Inc.	13,138	9,367	36,146	30,959
Preferred stock dividends	(2,798)	(2,798)	(8,395)	(8,394)
Net income available to common stockholders	10,340	6,569	27,751	22,565
Net income available to common stockholders	$ 10,340	$ 6,569	$ 27,751	$ 22,565
Per share net income available to common stockholders
Basic (in usd per share)	$ 0.44	$ 0.28	$ 1.17	$ 0.97
Diluted (in usd per share)	$ 0.44	$ 0.28	$ 1.17	$ 0.97

Consolidated Statement of Equit

Consolidated Statement of Equity (Unaudited) - USD ($) $ in Thousands	Total	Twinbrook Metro Station	Ashbrook Marketplace	Limited Partner	Limited PartnerTwinbrook Metro Station	Series D Cumulative Redeemable Preferred Stock	Series E Cumulative Redeemable Preferred Stock	Total Saul Centers, Inc.	Total Saul Centers, Inc.Twinbrook Metro Station	Total Saul Centers, Inc.Series D Cumulative Redeemable Preferred Stock	Total Saul Centers, Inc.Series E Cumulative Redeemable Preferred Stock	Preferred Stock	Common Stock	Additional Paid-in Capital	Partnership Units in Escrow	Partnership Units in EscrowTwinbrook Metro Station	Distributions in Excess of Accumulated Earnings	Distributions in Excess of Accumulated EarningsSeries D Cumulative Redeemable Preferred Stock	Distributions in Excess of Accumulated EarningsSeries E Cumulative Redeemable Preferred Stock	Noncontrolling Interests	Noncontrolling InterestsAshbrook Marketplace	Noncontrolling InterestsLimited Partner	Noncontrolling InterestsLimited PartnerTwinbrook Metro Station
Beginning Balance at Dec. 31, 2019	$ 443,356							$ 374,981				$ 185,000	$ 232	$ 410,926	$ 0		$ (221,177)			$ 68,375
Issuance of shares of common stock:
Issuance of shares pursuant to dividend reinvestment plan	4,081			$ 734				4,081					1	4,080								$ 734
Issuance of shares due to exercise of employee stock options and issuance of directors’ deferred shares	956							956						956
Net income	16,829							13,264									13,264			3,565
Distributions payable preferred stock:
Preferred stock distributions						$ (1,148)	$ (1,650)			$ (1,148)	$ (1,650)							$ (1,148)	$ (1,650)
Distributions payable, common stock and partnership units	(16,552)							(12,364)									(12,364)			(4,188)
Ending Balance at Mar. 31, 2020	446,606							378,120				185,000	233	415,962	0		(223,075)			68,486
Beginning Balance at Dec. 31, 2019	443,356							374,981				185,000	232	410,926	0		(221,177)			68,375
Issuance of shares of common stock:
Net income	38,640
Ending Balance at Sep. 30, 2020	431,617							367,018				185,000	234	417,504	0		(235,720)			64,599
Beginning Balance at Mar. 31, 2020	446,606							378,120				185,000	233	415,962	0		(223,075)			68,486
Issuance of shares of common stock:
Issuance of shares pursuant to dividend reinvestment plan	407							407						407
Issuance of shares due to exercise of employee stock options and issuance of directors’ deferred shares	424							424						424
Net income	10,208							8,328									8,328			1,880
Distributions payable preferred stock:
Preferred stock distributions						(1,148)	(1,650)			(1,148)	(1,650)							(1,148)	(1,650)
Distributions payable, common stock and partnership units	(16,561)							(12,373)									(12,373)			(4,188)
Ending Balance at Jun. 30, 2020	438,286							372,108				185,000	233	416,793	0		(229,918)			66,178
Issuance of shares of common stock:
Issuance of shares pursuant to dividend reinvestment plan	422							422					1	421
Issuance of shares due to exercise of employee stock options and issuance of directors’ deferred shares	290							290					0	290
Issuance of partnership units pursuant to dividend reinvestment plan	380																			380
Net income	11,603							9,367									9,367			2,236
Distributions payable preferred stock:
Preferred stock distributions						(1,148)	(1,650)			(1,148)	(1,650)							(1,148)	(1,650)
Distributions payable, common stock and partnership units	(16,566)							(12,371)									(12,371)			(4,195)
Ending Balance at Sep. 30, 2020	431,617							367,018				185,000	234	417,504	0		(235,720)			64,599
Beginning Balance at Dec. 31, 2020	427,533							364,325				185,000	235	420,625	0		(241,535)			63,208
Issuance of shares of common stock:
Issuance of shares pursuant to dividend reinvestment plan	2,840			575				2,840					1	2,839								575
Issuance of shares due to exercise of employee stock options and issuance of directors’ deferred shares	323							323						323
Stock issued during period, value, acquisitions		$ 79,300							$ 79,300							$ 79,300
Net income	12,795							10,262									10,262			2,533
Distributions payable preferred stock:
Preferred stock distributions						(1,148)	(1,650)			(1,148)	(1,650)							(1,148)	(1,650)
Distributions payable, common stock and partnership units	(16,706)							(12,488)									(12,488)			(4,218)
Ending Balance at Mar. 31, 2021	503,862							441,764				185,000	236	423,787	79,300		(246,559)			62,098
Beginning Balance at Dec. 31, 2020	427,533							364,325				185,000	235	420,625	0		(241,535)			63,208
Issuance of shares of common stock:
Net income	45,799
Ending Balance at Sep. 30, 2021	529,607							442,765				185,000	237	430,537	79,300		(252,309)			86,842
Beginning Balance at Mar. 31, 2021	503,862							441,764				185,000	236	423,787	79,300		(246,559)			62,098
Issuance of shares of common stock:
Issuance of shares pursuant to dividend reinvestment plan	2,855			$ 585				2,855						2,855								$ 585
Issuance of shares due to exercise of employee stock options and issuance of directors’ deferred shares	705							705						705
Stock issued during period, value, acquisitions			$ 4,320		$ 21,500																$ 4,320		$ 21,500
Net income	16,119							12,746									12,746			3,373
Distributions payable preferred stock:
Preferred stock distributions						(1,149)	(1,650)			(1,149)	(1,650)							(1,149)	(1,650)
Distributions payable, common stock and partnership units	(17,694)							(13,000)									(13,000)			(4,694)
Ending Balance at Jun. 30, 2021	529,453							442,271				185,000	236	427,347	79,300		(249,612)			87,182
Issuance of shares of common stock:
Issuance of shares pursuant to dividend reinvestment plan	2,897							2,897					1	2,896
Issuance of shares due to exercise of employee stock options and issuance of directors’ deferred shares	294							294					0	294
Issuance of partnership units pursuant to dividend reinvestment plan	615																			615
Net income	16,885							13,138									13,138			3,747
Distributions payable preferred stock:
Preferred stock distributions						$ (1,148)	$ (1,650)			$ (1,148)	$ (1,650)							$ (1,148)	$ (1,650)
Distributions payable, common stock and partnership units	(17,739)							(13,037)									(13,037)			(4,702)
Ending Balance at Sep. 30, 2021	$ 529,607							$ 442,765				$ 185,000	$ 237	$ 430,537	$ 79,300		$ (252,309)			$ 86,842

Consolidated Statement of Equ_2

Consolidated Statement of Equity (Parenthetical) - $ / shares	3 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Shares pursuant to dividend reinvestment plan	65,171,000	68,206,000	96,268	14,525,000	12,627,000	83,978
Shares due to exercise of employee stock options and issuance of directors' deferred stock	743,000	6,038,000	910	984,000	3,109,000	11,745
Issuance of partnership units pursuant to dividend reinvestment plan (in shares)	13,841,000			13,108,000
Limited Partner
Shares pursuant to dividend reinvestment plan		13,978,000	19,493			15,101
Twinbrook Metro Station
Number of partnership units issued in transaction (in shares)		469,740,000	1,416,071
Ashbrook Marketplace
Number of partnership units issued in transaction (in shares)		93,674,000
Dividend Distributions Payable
Distributions payable common stock, per share (in usd per share)	$ 0.55	$ 0.55	$ 0.53	$ 0.53	$ 0.53	$ 0.53
Distributions partnership units, per unit (in usd per share)	0.55	0.55	0.53	0.53	0.53	0.53
Series D Cumulative Redeemable Preferred Stock | Dividend Distributions Payable
Distributions payable on preferred stock, per share (in usd per share)	38.28	38.28	38.28	38.28	38.28	38.28
Series E Cumulative Redeemable Preferred Stock | Dividend Distributions Payable
Distributions payable on preferred stock, per share (in usd per share)	$ 37.50	$ 37.50	$ 37.50	$ 37.50	$ 37.50	$ 37.50

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net income		$ 45,799,000	$ 38,640,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of lease costs		37,852,000	37,593,000
Amortization of deferred debt costs		1,237,000	1,163,000
Compensation costs of stock and option grants		1,197,000	1,141,000
Credit losses on operating lease receivables		802,000	4,162,000
(Increase) decrease in accounts receivable and accrued income		2,260,000	(17,552,000)
Additions to deferred leasing costs		(1,316,000)	(7,383,000)
Increase in other assets		(4,124,000)	(2,286,000)
Increase in accounts payable, accrued expenses and other liabilities		2,432,000	3,871,000
Increase (decrease) in deferred income		2,923,000	(2,579,000)
Net cash provided by operating activities		89,062,000	56,770,000
Cash flows from investing activities:
Payments to Acquire Other Real Estate	[1],[2],[3]	(9,011,000)	0
Additions to real estate investments		(14,593,000)	(13,665,000)
Additions to development and redevelopment projects		(15,227,000)	(34,698,000)
Net cash used in investing activities		(38,831,000)	(48,363,000)
Cash flows from financing activities:
Proceeds from notes payable		0	52,100,000
Repayments on notes payable		(33,670,000)	(37,431,000)
Repayments on revolving credit facility		(42,500,000)	(53,000,000)
Proceeds from construction loan		2,430,000	32,928,000
Additions to deferred debt costs		(3,474,000)	(1,196,000)
Proceeds from the issuance of:
Common stock		8,717,000	5,440,000
Partnership units (1) (2) (3)	[1],[2],[3]	1,775,000	1,114,000
Distributions to:
Common stockholders		(37,926,000)	(37,012,000)
Noncontrolling interests		(13,127,000)	(12,556,000)
Net cash provided by (used in) financing activities		(65,170,000)	31,993,000
Net increase (decrease) in cash and cash equivalents		(14,939,000)	40,400,000
Cash and cash equivalents, beginning of period		26,856,000	13,905,000
Cash and cash equivalents, end of period		11,917,000	54,305,000
Supplemental disclosure of cash flow information:
Cash paid for interest		33,738,000	32,951,000
Increase (decrease) in accrued real estate investments and development costs		504,000	(11,196,000)
Secured Debt
Cash flows from financing activities:
Proceeds from revolving credit facility		25,000,000	0
Revolving Credit Facility
Cash flows from financing activities:
Proceeds from revolving credit facility		36,000,000	90,000,000
Twinbrook Quarter
Supplemental disclosure of cash flow information:
Limited partnership units issued		79,300
Twinbrook Metro Station Leasehold Interest
Supplemental disclosure of cash flow information:
Limited partnership units issued		21,500
Ashbrook Marketplace
Supplemental disclosure of cash flow information:
Limited partnership units issued		4,320
Series D Cumulative Redeemable Preferred Stock
Distributions to:
Preferred stockholders		(3,445,000)	(3,444,000)
Series E Cumulative Redeemable Preferred Stock
Distributions to:
Preferred stockholders		$ (4,950,000)	$ (4,950,000)
[1]	The 2021 acquisition of real estate and proceeds from the issuance of partnership units each excludes $21,500 in connection with the contribution of the Twinbrook Quarter leasehold interest in exchange for limited partnership units. See Notes 3 and 4 to the Consolidated Financial Statements.
[2]	The 2021 acquisition of real estate and proceeds from the issuance of partnership units each excludes $4,320 in connection with the issuance of additional limited partnership units to B. F. Saul Real Estate Investment Trust as additional consideration pursuant to the terms of the 2016 contribution agreement, as amended, related to Ashbrook Marketplace. See Note 7 to the Consolidated Financial Statements.
[3]	The 2021 acquisition of real estate and proceeds from the issuance of partnership units each excludes $79,300 in connection with the contribution of Twinbrook Quarter by the B. F. Saul Real Estate Investment Trust in exchange for limited partnership units that are held in escrow. See Notes 3 and 4 to the Consolidated Financial Statements.

Organization, Basis of Presenta

Organization, Basis of Presentation	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Basis of Presentation	Organization, Basis of Presentation Saul Centers, Inc. (“Saul Centers”) was incorporated under the Maryland General Corporation Law on June 10, 1993, and operates as a real estate investment trust (a “REIT”) under the Internal Revenue Code of 1986, as amended (the “Code”). The Company is required to annually distribute at least 90% of its REIT taxable income (excluding net capital gains) to its stockholders and meet certain organizational and other requirements. Saul Centers has made and intends to continue to make regular quarterly distributions to its stockholders. Saul Centers, together with its wholly-owned subsidiaries and the limited partnerships of which Saul Centers or one of its subsidiaries is the sole general partner, are referred to collectively as the “Company.” B. Francis Saul II serves as Chairman of the Board of Directors and Chief Executive Officer of Saul Centers. The Company, which conducts all of its activities through its subsidiaries, Saul Holdings Limited Partnership, a Maryland limited partnership (the “Operating Partnership”) and two subsidiary limited partnerships (the “Subsidiary Partnerships,” and, collectively with the Operating Partnership, the “Partnerships”), engages in the ownership, operation, management, leasing, acquisition, renovation, expansion, development and financing of community and neighborhood shopping centers and mixed-use properties, primarily in the Washington, DC/Baltimore metropolitan area. As of September 30, 2021, the Company’s properties (the “Current Portfolio Properties”) consisted of 50 shopping center properties (the “Shopping Centers”), seven mixed-use properties, which are comprised of office, retail and multi-family residential uses (the “Mixed-Use Properties”) and four (non-operating) development properties. Because the properties are located primarily in the Washington, DC/Baltimore metropolitan area, the Company is subject to a concentration of credit risk related to these properties. A majority of the Shopping Centers are anchored by one or more major tenants. As of September 30, 2021, 33 of the Shopping Centers were anchored by a grocery store and offer primarily day-to-day necessities and services. Giant Food, a tenant at 11 Shopping Centers, individually accounted for 5.3% of the Company's total revenue for the nine months ended September 30, 2021. No other tenant individually accounted for 2.5% or more of the Company’s total revenue, excluding lease termination fees, for the nine months ended September 30, 2021. The accompanying consolidated financial statements of the Company include the accounts of Saul Centers and its subsidiaries, including the Partnerships, which are majority owned by Saul Centers. Substantially all assets and liabilities of the Company as of September 30, 2021 and December 31, 2020, are comprised of the assets and liabilities of the Operating Partnership. Debt arrangements subject to recourse are described in Note 5. All significant intercompany balances and transactions have been eliminated in consolidation. The Operating Partnership is a variable interest entity ("VIE") because the limited partners do not have substantive kick-out or participating rights. The Company is the primary beneficiary of the Operating Partnership because it has the power to direct its activities and the rights to absorb 73.4% of its net income. Because the Operating Partnership is consolidated into the financial statements of the Company, classification of it as a VIE has no impact on the consolidated financial statements of the Company. The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. In the opinion of management, all adjustments necessary for the fair presentation of the financial position and results of operations of the Company for the interim periods have been included. All such adjustments are of a normal recurring nature. These consolidated financial statements and the accompanying notes should be read in conjunction with the audited consolidated financial statements of the Company for the year ended December 31, 2020, which are included in its Annual Report on Form 10-K. Certain information and note disclosures normally included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to those instructions. The results of operations for interim periods are not necessarily indicative of results to be expected for the year.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Our significant accounting policies disclosed in our Annual Report on Form 10-K for the year ended December 31, 2020 have not changed significantly in amount or composition. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. The most significant estimates and assumptions relate to collectability of operating lease receivables and impairment of real estate properties. Actual results could differ from those estimates. Accounts Receivable, Accrued Income and Allowance for Doubtful Accounts Accounts receivable represents amounts due from tenants, whether current or deferred, in accordance with the terms of their respective leases and base rent recognized on a straight-line basis. Individual leases are assessed for collectability and upon the determination that the collection of rents is not probable, accrued rent and accounts receivable are charged off, which is reflected as an adjustment to rental revenue. Revenue from leases where collection is not probable is recorded on a cash basis until collectability is determined to be probable. Further, we assess whether operating lease receivables, at the portfolio level, are appropriately valued based upon an analysis of balances outstanding, historical bad debt levels and current economic trends. As of September 30, 2021, $4.6 million of rents previously deferred have come due. Of the amounts that have come due, $4.5 million has been paid. At September 30, 2021 and December 31, 2020, accounts receivable was comprised of: (In thousands) September 30, 2021 December 31, 2020 Rents currently due $ 7,576 $ 13,321 Deferred rents 5,388 8,205 Straight-line rent 46,429 44,863 Other receivables 5,974 3,751 Allowance for doubtful accounts (3,512) (5,223) Total $ 61,855 $ 64,917 Reclassifications Certain reclassifications have been made to the prior year financial statements to conform to the presentation used for the nine months ended September 30, 2021.

Real Estate

Real Estate	9 Months Ended
	Sep. 30, 2021
Real Estate [Abstract]
Real Estate	Real Estate Construction In Progress Construction in progress includes land, preconstruction and development costs of active projects. Preconstruction costs include legal, zoning and permitting costs and other project carrying costs incurred prior to the commencement of construction. Development costs include direct construction costs and indirect costs incurred subsequent to the start of construction such as architectural, engineering, construction management and carrying costs consisting of interest, real estate taxes and insurance. During the nine months ended September 30, 2021, assets totaling $8.7 million were placed in service in conjunction with the substantial completion of The Waycroft. Construction in progress as of September 30, 2021 and December 31, 2020, is composed of the following: (In thousands) September 30, 2021 December 31, 2020 Twinbrook Quarter $ 127,348 $ — Hampden House 53,619 50,723 The Waycroft — 8,651 Ashbrook Marketplace — 153 Other 10,740 9,950 Total $ 191,707 $ 69,477 Leases We lease Shopping Centers and Mixed-Use Properties to lessees in exchange for monthly payments that cover rent, and, where applicable, reimbursement for property taxes, insurance, and certain property operating expenses. Our leases have been determined to be operating leases and generally range in term from one Some of our leases have termination options and/or extension options. Termination options allow the lessee and/or lessor to terminate the lease prior to the end of the lease term, provided certain conditions are met. Termination options generally require advance notification from the lessee and/or lessor and payment of a termination fee. Termination fees are recognized as revenue over the modified lease term. Extension options are subject to terms and conditions stated in the lease. An operating lease right of use asset and corresponding lease liability related to our headquarters lease are reflected in other assets and other liabilities, respectively. The lease expires on February 28, 2022, with one option to renew for an additional five years. The right of use asset and corresponding lease liability totaled $321,900 and $334,500, respectively, at September 30, 2021. Due to the business disruptions and challenges severely affecting the global economy caused by the novel strain of coronavirus (“COVID-19”) pandemic, many lessees have requested rent relief, including rent deferrals and other lease concessions. The lease modification guidance in Accounting Standards Update 2016-02, "Accounting for Leases" Deferred Leasing Costs Deferred leasing costs consist of commissions paid to third-party and internal leasing agents, internal costs such as payroll-related fringe benefits that are direct and incremental to successful commercial leases, amounts attributed to in-place leases associated with acquired properties and lease inducement costs. Effective with the adoption of ASU 2016-02 on January 1, 2019, all costs incurred prior to the execution of a lease are charged to expense and not capitalized. Unamortized deferred leasing costs are charged to expense if the applicable lease is terminated prior to expiration of the initial lease term. Deferred leasing costs are amortized over the term of the lease or remaining term of acquired leases. Collectively, deferred leasing costs totaled $24.6 million and $26.9 million, net of accumulated amortization of $47.7 million and $44.5 million, as of September 30, 2021 and December 31, 2020, respectively. Amortization expense, included in depreciation and amortization of lease costs in the Consolidated Statements of Operations, totaled $3.6 million and $4.0 million for the nine months ended September 30, 2021 and 2020, respectively. Real Estate Investment Properties Depreciation is calculated using the straight-line method and estimated useful lives of generally between 35 and 50 years for base buildings, or a shorter period if management determines that the building has a shorter useful life, and up to 20 years for certain other improvements that extend the useful lives. Leasehold improvement expenditures are capitalized when certain criteria are met, including when the Company supervises construction and will own the improvements. Tenant improvements are amortized, over the shorter of the lives of the related leases or the useful life of the improvements, using the straight-line method. Depreciation expense in the Consolidated Statements of Operations totaled $34.2 million and $33.6 million for the nine months ended September 30, 2021 and 2020, respectively. Repairs and maintenance expense totaled $10.2 million and $8.0 million for the nine months ended September 30, 2021 and 2020, respectively, and is included in property operating expenses in the Consolidated Statements of Operations. As of September 30, 2021, we have not identified any impairment triggering events, including the impact of COVID-19 and corresponding tenant requests for rent relief. Therefore, under applicable GAAP guidance, no impairment charges were recorded. Acquisitions On November 5, 2019, the Company entered into an agreement (the “Twinbrook Contribution Agreement”) to acquire from 1592 Rockville Pike LLC ("1592 Rockville Pike"), a wholly-owned subsidiary of the B. F. Saul Real Estate Investment Trust (the “Trust”), approximately 6.8 acres of land and its leasehold interest in approximately 1.3 acres of contiguous land, together in each case with the improvements located thereon, located at the Twinbrook Metro Station in Rockville, Maryland (the “Contributed Property”). The Contributed Property is immediately adjacent to approximately 10.3 acres owned by the Company. In exchange for the Contributed Property, the Company will issue to 1592 Rockville Pike 1,416,071 limited partnership units in the Operating Partnership. Title to the Contributed Property and the units were placed in escrow until certain conditions of the Twinbrook Contribution Agreement were satisfied. The units issued to 1592 Rockville Pike will remain in escrow until the conditions of the Twinbrook Contribution Agreement, as amended, are satisfied. Half of the units held in escrow were released on the October 18, 2021. The remaining units held in escrow are scheduled to be released on October 18, 2023. On March 5, 2021, the Company entered into an amendment to the Twinbrook Contribution Agreement in which it and 1592 Rockville Pike agreed to release to the Company from escrow the deed and assignment of the leasehold interest of the Contributed Property, as of that date. The Company also reimbursed 1592 Rockville Pike for certain expenses pursuant to the Twinbrook Contribution Agreement totaling $7.4 million. Acquisition costs totaled $1.2 million. The Company recorded a finance lease right-of-use asset of $19.4 million and corresponding lease liability of $19.4 million related to the leasehold interest assumed in the transaction. The incremental borrowing rate used to calculate the lease liability was 5.63%. On June 29, 2021, the third-party landlord under the ground lease contributed to the Company the fee simple interest in the land underlying the leasehold interest in exchange for 469,740 limited partnership units in the Operating Partnership, representing an aggregate value of $21.5 million. Acquisition costs were paid in cash and totaled $0.7 million. Accordingly, the finance lease right-of-use asset and finance lease liability were extinguished. Amortization expense and interest expense related to the lease totaled $104,000 and $362,800, respectively, for the nine months ended September 30, 2021.

Noncontrolling Interests - Hold

Noncontrolling Interests - Holders of Convertible Limited Partnership Units in the Operating Partnership	9 Months Ended
	Sep. 30, 2021
Noncontrolling Interest [Abstract]
Noncontrolling Interests - Holders of Convertible Limited Partnership Units in the Operating Partnership	Noncontrolling Interests - Holders of Convertible Limited Partnership Units in the Operating PartnershipAs of September 30, 2021, the B. F. Saul Company and certain other affiliated entities, each of which is controlled by B. Francis Saul II and his family members, (collectively, the “Saul Organization”) held an aggregate 25.1% limited partnership interest in the Operating Partnership represented by approximately 8.1 million convertible limited partnership units. These units are convertible into shares of Saul Centers’ common stock, at the option of the unit holder, on a one-for-one basis provided that, in accordance with the Company’s Articles of Incorporation, the rights may not be exercised at any time that the Saul Organization beneficially owns or will own after the exercise, directly or indirectly, in the aggregate more than 39.9% of the value of the outstanding common stock and preferred stock of Saul Centers (the “Equity Securities”). As of September 30, 2021, approximately 1.0 million units could be converted into shares of Saul Centers common stock. As of September 30, 2021, a third party investor holds a 1.5% limited partnership interest in the Operating Partnership represented by 469,740 convertible limited partnership units. At the option of the unit holder, these units are convertible into shares of Saul Centers’ common stock on a one-for-one basis; provided that, in lieu of the delivery of Saul Centers' common stock, Saul Centers may, in its sole discretion, deliver cash in an amount equal to the value of such Saul Centers' common stock. The impact of the aggregate 26.6% limited partnership interest in the Operating Partnership held by parties other than Saul Centers is reflected as Noncontrolling Interests in the accompanying consolidated financial statements. Weighted average fully diluted partnership units and common stock outstanding for the three months ended September 30, 2021 and 2020, was approximately 33.7 million and 31.3 million, respectively, and for the nine months ended September 30, 2021 and 2020, was approximately 32.9 million and 31.2 million, respectively. The 0.7 million limited partnership units remaining in escrow after October 18, 2021, in connection with the Twinbrook Contribution Agreement are not eligible to receive distributions from the Operating Partnership until such time as they are released from escrow.

Notes Payable, Revolving Credit

Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs	Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs The principal amount of the Company’s outstanding debt totaled approximately $1.1 billion at September 30, 2021, of which approximately $949.5 million was fixed-rate debt and approximately $198.0 million was variable rate debt outstanding under the credit facility. The carrying value of the properties collateralizing the notes payable totaled approximately $1.1 billion as of September 30, 2021. On August 31, 2021, the Company replaced its credit facility. The new credit facility, which can be used for working capital, property acquisitions, development projects or letters of credit, totals $525.0 million (the “New Facility”), of which $425.0 million is a revolving credit facility (the “Revolving Line”) and $100.0 million is a term loan (the “Term Loan”). The Revolving Line matures on August 29, 2025, which term may be extended by the Company for one additional year, subject to satisfaction of certain conditions. The Term Loan matures on February 26, 2027, and may not be extended. In general, loan availability under the New Facility is primarily determined by operating income from the Company’s existing unencumbered properties. Interest accrues at a rate of LIBOR plus a spread of 135 basis points to 195 basis points under the Revolving Line, and 130 basis points to 190 basis points under the Term Loan, each as determined by certain leverage tests. As of September 30, 2021, the applicable spread for borrowings is 140 basis points under the Revolving Line and 135 basis points under the Term Loan. Saul Centers and certain consolidated subsidiaries of the Operating Partnership have guaranteed the payment obligations of the Operating Partnership under the New Facility. Letters of credit may be issued under the revolving credit facility. On September 30, 2021, based on the value of the Company’s unencumbered properties, approximately $228.2 million was available under the Revolving Line, $98.0 million was outstanding and approximately $185,000 was committed for letters of credit. On January 5, 2021, the Company repaid in full the remaining principal balance of $6.1 million of the mortgage loan secured by Jamestown Place, which was scheduled to mature in February 2021. On June 11, 2021, the Company repaid in full the remaining principal balance of $5.0 million of the mortgage loan secured by Hunt Club Corners, which was scheduled to mature in August 2021. Saul Centers and certain consolidated subsidiaries of the Operating Partnership have guaranteed the payment obligations of the Operating Partnership under the credit facility. The Operating Partnership is the guarantor of (a) a portion of the Park Van Ness mortgage (approximately $3.3 million of the $65.1 million outstanding balance at September 30, 2021, which guarantee will be reduced to zero on October 1, 2021), (b) a portion of the Broadlands mortgage (approximately $3.7 million of the $29.9 million outstanding balance at September 30, 2021), (c) a portion of the Avenel Business Park mortgage (approximately $6.3 million of the $24.4 million outstanding balance at September 30, 2021), (d) a portion of The Waycroft mortgage (approximately $23.6 million of the $148.5 million outstanding balance at September 30, 2021), (e) the Ashbrook Marketplace mortgage (totaling $21.5 million at September 30, 2021), and (f) the mortgage secured by Kentlands Place, Kentlands Square I and Kentlands Pad (totaling $29.2 million at September 30, 2021). All other notes payable are non-recourse. At December 31, 2020, the principal amount of the Company’s outstanding debt totaled approximately $1.2 billion, of which $980.8 million was fixed rate debt and $179.5 million was variable rate debt, including $104.5 million outstanding under an unsecured revolving credit facility. The carrying value of the properties collateralizing the notes payable totaled approximately $1.2 billion as of December 31, 2020. At September 30, 2021, the scheduled maturities of debt, including scheduled principal amortization, for years ending December 31, were as follows: (In thousands) Balloon Scheduled Total October 1 through December 31, 2021 $ — $ 7,679 $ 7,679 2022 36,502 31,016 67,518 2023 9,225 31,479 40,704 2024 66,164 30,876 97,040 2025 118,363 (a) 27,860 146,223 2026 134,088 24,333 158,421 Thereafter 537,673 92,253 629,926 Principal amount $ 902,015 $ 245,496 1,147,511 Unamortized deferred debt costs 11,576 Net $ 1,135,935 (a) Includes $98.0 million outstanding under the Revolving Line. Deferred debt costs consist of fees and costs incurred to obtain long-term financing, construction financing and the credit facility. These fees and costs are being amortized on a straight-line basis over the terms of the respective loans or agreements, which approximates the effective interest method. Deferred debt costs totaled $11.6 million and $9.3 million, net of accumulated amortization of $7.2 million and $8.7 million, at September 30, 2021 and December 31, 2020, respectively, and are reflected as a reduction of the related debt in the Consolidated Balance Sheets. Interest expense, net and amortization of deferred debt costs for the three and nine months ended September 30, 2021 and 2020, were as follows: Three Months Ended September 30, Nine Months Ended September 30, (In thousands) 2021 2020 2021 2020 Interest incurred $ 12,481 $ 12,933 $ 38,062 $ 38,788 Amortization of deferred debt costs 425 402 1,237 1,163 Capitalized interest (1,991) (909) (4,734) (5,813) Interest expense 10,915 12,426 34,565 34,138 Less: Interest income 1 28 6 127 Interest expense, net and amortization of deferred debt costs $ 10,914 $ 12,398 $ 34,559 $ 34,011

Equity

Equity	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Equity	Equity The consolidated statements of operations for the nine months ended September 30, 2021 and 2020, reflect noncontrolling interests of $9.7 million and $7.7 million, respectively, representing income attributable to limited partnership units not held by Saul Centers. At September 30, 2021, the Company had outstanding 3.0 million depositary shares, each representing 1/100th of a share of 6.125% Series D Cumulative Redeemable Preferred Stock (the "Series D Stock"). The depositary shares may be redeemed at the Company’s option, in whole or in part, on or after January 23, 2023, at the $25.00 liquidation preference, plus accrued but unpaid dividends to but not including the redemption date. The depositary shares pay an annual dividend of $1.53125 per share, equivalent to 6.125% of the $25.00 liquidation preference. The Series D Stock has no stated maturity, is not subject to any sinking fund or mandatory redemption and is not convertible into any other securities of the Company except in connection with certain changes in control or delisting events. Investors in the depositary shares generally have no voting rights, but will have limited voting rights if the Company fails to pay dividends for six or more quarters (whether or not declared or consecutive) and in certain other events. At September 30, 2021, the Company had outstanding 4.4 million depositary shares, each representing 1/100th of a share of 6.000% Series E Cumulative Redeemable Preferred Stock (the “Series E Stock”). The depositary shares may be redeemed at the Company’s option, in whole or in part, on or after September 17, 2024, at the $25.00 liquidation preference, plus accrued but unpaid dividends to but not including the redemption date. The depositary shares pay an annual dividend of $1.50 per share, equivalent to 6.000% of the $25.00 liquidation preference. The Series E Stock has no stated maturity, is not subject to any sinking fund or mandatory redemption and is not convertible into any other securities of the Company except in connection with certain changes in control or delisting events. Investors in the depositary shares generally have no voting rights, but will have limited voting rights if the Company fails to pay dividends for six or more quarters (whether or not declared or consecutive) and in certain other events. Per Share Data Per share data for net income (basic and diluted) is computed using weighted average shares of common stock. Convertible limited partnership units and employee stock options are the Company’s potentially dilutive securities. For all periods presented, the convertible limited partnership units are non-dilutive. The following table sets forth, for the indicated periods, weighted averages of the number of common shares outstanding, basic and dilutive, the effect of dilutive options and the number of options which are not dilutive because the average price of the Company's common stock was less than the exercise prices. The treasury stock method was used to measure the effect of the dilution. Three months ended September 30, Nine months ended September 30, (In thousands) 2021 2020 2021 2020 Weighted average common stock outstanding-Basic 23,692 23,353 23,619 23,329 Effect of dilutive options 4 — 2 1 Weighted average common stock outstanding-Diluted 23,696 23,353 23,621 23,330 Non-dilutive options 1,350 1,516 1,474 1,418 Years non-dilutive options were issued 2014 through 2020 2011 through 2020 2011 and 2014 through 2020 2014 through 2020

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Chairman and Chief Executive Officer, the President and Chief Operating Officer, the Executive Vice President-Chief Legal and Administrative Officer and the Senior Vice President-Chief Accounting Officer and Treasurer of the Company are also officers of various members of the Saul Organization and their management time is shared with the Saul Organization. Their annual compensation is fixed by the Compensation Committee of the Board of Directors, with the exception of the Senior Vice President-Chief Accounting Officer and Treasurer whose share of annual compensation allocated to the Company is determined by the shared services agreement (described below). The Company participates in a multiemployer 401K plan with entities in the Saul Organization which covers those full-time employees who meet the requirements as specified in the plan. Company contributions, which are included in general and administrative expense or property operating expenses in the Consolidated Statements of Operations, at the discretionary amount of up to 6% of the employee’s cash compensation, subject to certain limits, were $328,500 and $255,200 for the nine months ended September 30, 2021 and 2020, respectively. All amounts contributed by employees and the Company are fully vested. The Company also participates in a multiemployer nonqualified deferred compensation plan with entities in the Saul Organization which covers those full-time employees who meet the requirements as specified in the plan. According to the plan, which can be modified or discontinued at any time, participating employees defer 2% of their compensation in excess of a specified amount. For the nine months ended September 30, 2021 and 2020, the Company credited to employee accounts $120,800 and $164,800, respectively, which is the sum of accrued earnings and up to three times the amount deferred by employees and is included in general and administrative expense. All amounts contributed by employees and credited by the Company are fully vested. The cumulative unfunded liability under this plan was $3.0 million and $2.9 million, at September 30, 2021 and December 31, 2020, respectively, and is included in accounts payable, accrued expenses and other liabilities in the Consolidated Balance Sheets. The Company and the Saul Organization are parties to a shared services agreement (the “Agreement”) that provides for the sharing of certain personnel and ancillary functions such as computer hardware, software, and support services and certain direct and indirect administrative personnel. The method for determining the cost of the shared services is provided for in the Agreement and is based upon head count, estimates of usage or estimates of time incurred, as applicable. The terms of the Agreement and the payments made thereunder are deemed reasonable by management and are reviewed annually by the Audit Committee of the Board of Directors, which consists entirely of independent directors. Net billings by the Saul Organization for the Company’s share of these ancillary costs and expenses for the nine months ended September 30, 2021 and 2020, which included rental expense for the Company’s headquarters lease, totaled approximately $5.9 million and $6.0 million, respectively. The amounts are generally expensed as incurred and are primarily reported as general and administrative expenses in the Consolidated Statements of Operations. As of September 30, 2021 and December 31, 2020, accounts payable, accrued expenses and other liabilities included approximately $883,900 and $782,700, respectively, representing amounts due to the Saul Organization for the Company’s share of these ancillary costs and expenses. On March 5, 2021, the Company acquired from 1592 Rockville Pike, approximately 6.8 acres of land and its leasehold interest in approximately 1.3 acres of contiguous land, together in each case with the improvements located thereon, located at the Twinbrook Metro Station in Rockville, Maryland. See Notes 3 and 4. In August 2016, the Company entered into an agreement (the "Ashbrook Contribution Agreement") to acquire from the Trust approximately 13.7 acres of land located at the intersection of Ashburn Village Boulevard and Russell Branch Parkway in Ashburn, Virginia. The transaction closed on May 9, 2018, and the Company issued 176,680 limited partnership units to the Trust. The Company constructed a shopping center, Ashbrook Marketplace. On June 30, 2021, the Company issued 93,674 additional limited partnership units as additional consideration to the Trust in accordance with the Ashbrook Contribution Agreement, as amended. The Company subleases its corporate headquarters space from a member of the Saul Organization. The lease commenced in March 2002, expires in 2022, and provides for base rent increases of 3% per year, with payment of a pro-rata share of operating expenses over a base year amount. The Agreement requires each party to pay an allocation of total rental payments based on a percentage proportionate to the number of employees employed by each party. The Company’s rent expense for its headquarters location was $611,200 and $609,200 for the nine months ended September 30, 2021 and 2020, respectively, and is included in general and administrative expense. The B. F. Saul Insurance Agency, Inc., a subsidiary of the B. F. Saul Company and a member of the Saul Organization, is a general insurance agency that receives commissions and fees in connection with the Company’s insurance program. Such commissions and fees amounted to $280,700 and $320,300 for the nine months ended September 30, 2021 and 2020, respectively.

Stock-based Employee Compensati

Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors	Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors In 2004, the Company established a stock incentive plan (the "Plan"), as amended. Under the Plan, options are granted at an exercise price not less than the market value of the common stock on the date of grant and expire ten years from the date of grant. Officer options vest ratably over four years following the grant and are charged to expense using the straight-line method over the vesting period. Director options vest immediately and are charged to expense as of the date of grant. The Company uses the fair value method to value and account for employee stock options. The fair value of options granted is determined at the time of the grant using the Black-Scholes model, a widely used method for valuing stock-based employee compensation, and the following assumptions: (1) Expected Volatility determined using the most recent trading history of the Company’s common stock (month-end closing prices) corresponding to the average expected term of the options; (2) Average Expected Term of the options based on prior exercise history, scheduled vesting and the expiration date; (3) Expected Dividend Yield determined by management after considering the Company’s current and historic dividend yield, the Company’s yield in relation to other retail REITs and the Company’s market yield at the grant date; and (4) a Risk-free Interest Rate based upon the market yields of US Treasury obligations with maturities corresponding to the average expected term of the options at the grant date. The Company amortizes the value of options granted ratably over the vesting period and includes the amounts as compensation expense in general and administrative expenses. Pursuant to the Plan, the Compensation Committee established a Deferred Compensation Plan for Directors for the benefit of the Company’s directors and their beneficiaries, which replaced a previous Deferred Compensation and Stock Plan for Directors. Annually, directors are given the ability to make an election to defer all or part of their fees and have the option to have their fees paid in cash, in shares of common stock or in a combination of cash and shares of common stock upon separation from the Board. If a director elects to have their fees paid in stock, fees earned during a calendar quarter are aggregated and divided by the closing market price of the Company’s common stock on the first trading day of the following quarter to determine the number of shares to be credited to the director. During the nine months ended September 30, 2021, 7,429 shares were credited to director's deferred fee accounts and 7,874 shares were issued. As of September 30, 2021, the director's deferred fee accounts comprise 118,183 shares. Effective May 7, 2021, the Company granted 250,500 options to its directors and certain officers. The following table summarizes the assumptions used in the valuation of the 2021 and 2020 option grants. During the nine months ended September 30, 2021, stock option expense totaling $1.0 million was included in general and administrative expense in the Consolidated Statements of Operations. As of September 30, 2021, the estimated future expense related to unvested stock options was $2.0 million. Directors Officers Grant date April 24, 2020 May 7, 2021 April 24, 2020 May 7, 2021 Exercise price $ 50.00 $ 43.89 $ 50.00 $ 43.89 Volatility 0.258 0.297 0.240 0.275 Expected life (years) 5.0 5.0 7.0 7.0 Assumed yield 3.80 % 4.96 % 3.85 % 4.97 % Risk-free rate 0.36 % 0.77 % 0.51 % 1.24 % The table below summarizes the option activity for the nine months ended September 30, 2021: Number of Weighted Aggregate Outstanding at January 1 1,502,670 $ 52.86 $ — Granted 250,500 43.89 — Exercised (3,000) 41.82 3,450 Expired/Forfeited (87,000) 53.60 — Outstanding at September 30 1,663,170 51.49 171,250 Exercisable at September 30 1,137,295 52.89 133,340

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial InstrumentsThe carrying values of cash and cash equivalents, accounts receivable, accounts payable and accrued expenses are reasonable estimates of their fair value. The aggregate fair value of the notes payable with fixed-rate payment terms was determined using Level 3 data in a discounted cash flow approach, which is based upon management’s estimate of borrowing rates and loan terms currently available to the Company for fixed-rate financing and, assuming long-term market interest rates of approximately 3.60% and 3.40%, would be approximately $937.3 million and $981.0 million, respectively, compared to the principal balance of $949.5 million and $980.8 million at September 30, 2021 and December 31, 2020, respectively. A change in any of the significant inputs may lead to a change in the Company’s fair value measurement of its debt.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and ContingenciesNeither the Company nor the current portfolio properties are subject to any material litigation, nor, to management’s knowledge, is any material litigation currently threatened against the Company, other than routine litigation and administrative proceedings arising in the ordinary course of business. Management believes that these items, individually or in the aggregate, will not have a material adverse impact on the Company or the current portfolio properties.

Business Segments

Business Segments	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Business Segments	Business Segments The Company has two reportable business segments: Shopping Centers and Mixed-Use Properties. The accounting policies of the segments are the same as those described in the summary of significant accounting policies (see Note 2). The Company evaluates performance based upon income and cash flows from real estate of the combined properties in each segment. All of our properties within each segment generate similar types of revenues and expenses related to tenant rent, reimbursements and operating expenses. Although services are provided to a variety of tenants, the types of services provided to them are similar within each segment. The properties in each portfolio have similar economic characteristics and the nature of the products and services provided to our tenants and the method to distribute such services are consistent throughout the portfolio. Certain reclassifications have been made to prior year information to conform to the 2021 presentation. (In thousands) Shopping Mixed-Use Corporate Consolidated Three months ended September 30, 2021 Real estate rental operations: Revenue $ 42,485 $ 17,771 $ — $ 60,256 Expenses (8,640) (6,724) — (15,364) Income from real estate 33,845 11,047 — 44,892 Interest expense, net and amortization of deferred debt costs — — (10,914) (10,914) Depreciation and amortization of lease costs (7,203) (5,264) — (12,467) General and administrative — — (4,626) (4,626) Net income (loss) $ 26,642 $ 5,783 $ (15,540) $ 16,885 Capital investment $ 2,629 $ 8,722 $ — $ 11,351 Total assets $ 960,247 $ 766,761 $ 12,492 $ 1,739,500 Three months ended September 30, 2020 Real estate rental operations: Revenue $ 40,336 $ 16,424 $ — $ 56,760 Expenses (8,755) (6,184) — (14,939) Income from real estate 31,581 10,240 — 41,821 Interest expense, net and amortization of deferred debt costs — — (12,398) (12,398) Depreciation and amortization of lease costs (8,169) (5,544) — (13,713) General and administrative — — (4,107) (4,107) Net income (loss) $ 23,412 $ 4,696 $ (16,505) $ 11,603 Capital investment $ 2,733 $ 6,703 $ — $ 9,436 Total assets $ 982,381 $ 643,395 $ 55,598 $ 1,681,374 (In thousands) Shopping Mixed-Use Corporate Consolidated Nine Months Ended September 30, 2021 Real estate rental operations: Revenue $ 126,935 $ 52,050 $ — $ 178,985 Expenses (27,087) (19,454) — (46,541) Income from real estate 99,848 32,596 — 132,444 Interest expense, net and amortization of deferred debt costs — — (34,559) (34,559) Depreciation and amortization of deferred leasing costs (21,639) (16,213) — (37,852) General and administrative — — (14,234) (14,234) Net income (loss) $ 78,209 $ 16,383 $ (48,793) $ 45,799 Capital investment $ 8,200 $ 30,631 $ — $ 38,831 Total assets $ 960,247 $ 766,761 $ 12,492 $ 1,739,500 Nine Months Ended September 30, 2020 Real estate rental operations: Revenue $ 120,236 $ 46,687 $ — $ 166,923 Expenses (26,041) (16,848) — (42,889) Income from real estate 94,195 29,839 — 124,034 Interest expense, net and amortization of deferred debt costs — — (34,011) (34,011) Depreciation and amortization of deferred leasing costs (22,812) (14,781) — (37,593) General and administrative — — (13,790) (13,790) Net income (loss) $ 71,383 $ 15,058 $ (47,801) $ 38,640 Capital investment $ 11,622 $ 36,741 $ — $ 48,363 Total assets $ 982,381 $ 643,395 $ 55,598 $ 1,681,374

Impact of COVID-19

Impact of COVID-19	9 Months Ended
	Sep. 30, 2021
Unusual or Infrequent Items, or Both [Abstract]
Impact of COVID-19	Impact of COVID-19 On March 11, 2020, the World Health Organization declared a novel strain of coronavirus ("COVID-19") a pandemic, and on March 13, 2020, the United States declared a national emergency with respect to COVID-19. As a result, the COVID-19 pandemic is negatively affecting almost every industry directly or indirectly. The actions taken by federal, state and local governments to mitigate the spread of COVID-19 by ordering closure of nonessential businesses and ordering residents to generally stay at home, and subsequent phased re-openings, resulted in many of our tenants announcing mandated or temporary closures of their operations and/or requesting adjustments to their lease terms. While most of our tenants have re-opened their businesses, there remains significant uncertainty around the long-term economic impact of the COVID-19 pandemic, which could have a material and adverse effect on or cause disruption to our business or financial condition, results from operations, cash flows and the market value and trading price of our securities.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsThe Company has reviewed operating activities for the period subsequent to September 30, 2021, and determined there are no subsequent events required to be disclosed.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Nature of Operations	The Company, which conducts all of its activities through its subsidiaries, Saul Holdings Limited Partnership, a Maryland limited partnership (the “Operating Partnership”) and two subsidiary limited partnerships (the “Subsidiary Partnerships,” and, collectively with the Operating Partnership, the “Partnerships”), engages in the ownership, operation, management, leasing, acquisition, renovation, expansion, development and financing of community and neighborhood shopping centers and mixed-use properties, primarily in the Washington, DC/Baltimore metropolitan area. As of September 30, 2021, the Company’s properties (the “Current Portfolio Properties”) consisted of 50 shopping center properties (the “Shopping Centers”), seven mixed-use properties, which are comprised of office, retail and multi-family residential uses (the “Mixed-Use Properties”) and four (non-operating) development properties.
Principles of Consolidation	The accompanying consolidated financial statements of the Company include the accounts of Saul Centers and its subsidiaries, including the Partnerships, which are majority owned by Saul Centers. Substantially all assets and liabilities of the Company as of September 30, 2021 and December 31, 2020, are comprised of the assets and liabilities of the Operating Partnership. Debt arrangements subject to recourse are described in Note 5. All significant intercompany balances and transactions have been eliminated in consolidation.
Consolidation, Variable Interest Entity	The Operating Partnership is a variable interest entity ("VIE") because the limited partners do not have substantive kick-out or participating rights. The Company is the primary beneficiary of the Operating Partnership because it has the power to direct its activities and the rights to absorb 73.4% of its net income. Because the Operating Partnership is consolidated into the financial statements of the Company, classification of it as a VIE has no impact on the consolidated financial statements of the Company.
Basis of Presentation	The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. In the opinion of management, all adjustments necessary for the fair presentation of the financial position and results of operations of the Company for the interim periods have been included. All such adjustments are of a normal recurring nature. These consolidated financial statements and the accompanying notes should be read in conjunction with the audited consolidated financial statements of the Company for the year ended December 31, 2020, which are included in its Annual Report on Form 10-K. Certain information and note disclosures normally included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to those instructions. The results of operations for interim periods are not necessarily indicative of results to be expected for the year.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. The most significant estimates and assumptions relate to collectability of operating lease receivables and impairment of real estate properties. Actual results could differ from those estimates.
Accounts Receivable, Accrued Income and Allowance for Doubtful Accounts	Accounts Receivable, Accrued Income and Allowance for Doubtful AccountsAccounts receivable represents amounts due from tenants, whether current or deferred, in accordance with the terms of their respective leases and base rent recognized on a straight-line basis. Individual leases are assessed for collectability and upon the determination that the collection of rents is not probable, accrued rent and accounts receivable are charged off, which is reflected as an adjustment to rental revenue. Revenue from leases where collection is not probable is recorded on a cash basis until collectability is determined to be probable. Further, we assess whether operating lease receivables, at the portfolio level, are appropriately valued based upon an analysis of balances outstanding, historical bad debt levels and current economic trends.
Reclassifications	Reclassifications Certain reclassifications have been made to the prior year financial statements to conform to the presentation used for the nine months ended September 30, 2021.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - (Tables)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Schedule of Accounts Receivable	At September 30, 2021 and December 31, 2020, accounts receivable was comprised of: (In thousands) September 30, 2021 December 31, 2020 Rents currently due $ 7,576 $ 13,321 Deferred rents 5,388 8,205 Straight-line rent 46,429 44,863 Other receivables 5,974 3,751 Allowance for doubtful accounts (3,512) (5,223) Total $ 61,855 $ 64,917

Real Estate - (Tables)

Real Estate - (Tables)	9 Months Ended
	Sep. 30, 2021
Real Estate [Abstract]
Schedule of Construction in Progress	Construction in progress as of September 30, 2021 and December 31, 2020, is composed of the following: (In thousands) September 30, 2021 December 31, 2020 Twinbrook Quarter $ 127,348 $ — Hampden House 53,619 50,723 The Waycroft — 8,651 Ashbrook Marketplace — 153 Other 10,740 9,950 Total $ 191,707 $ 69,477

Notes Payable, Revolving Cred_2

Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Scheduled Maturities of Debt, Including Scheduled Principal Amortization	At September 30, 2021, the scheduled maturities of debt, including scheduled principal amortization, for years ending December 31, were as follows: (In thousands) Balloon Scheduled Total October 1 through December 31, 2021 $ — $ 7,679 $ 7,679 2022 36,502 31,016 67,518 2023 9,225 31,479 40,704 2024 66,164 30,876 97,040 2025 118,363 (a) 27,860 146,223 2026 134,088 24,333 158,421 Thereafter 537,673 92,253 629,926 Principal amount $ 902,015 $ 245,496 1,147,511 Unamortized deferred debt costs 11,576 Net $ 1,135,935 (a) Includes $98.0 million outstanding under the Revolving Line.
Interest Expense and Amortization of Deferred Debt Costs	Interest expense, net and amortization of deferred debt costs for the three and nine months ended September 30, 2021 and 2020, were as follows: Three Months Ended September 30, Nine Months Ended September 30, (In thousands) 2021 2020 2021 2020 Interest incurred $ 12,481 $ 12,933 $ 38,062 $ 38,788 Amortization of deferred debt costs 425 402 1,237 1,163 Capitalized interest (1,991) (909) (4,734) (5,813) Interest expense 10,915 12,426 34,565 34,138 Less: Interest income 1 28 6 127 Interest expense, net and amortization of deferred debt costs $ 10,914 $ 12,398 $ 34,559 $ 34,011

Equity (Tables)

Equity (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Schedule of Weighted Average Number of Shares	The following table sets forth, for the indicated periods, weighted averages of the number of common shares outstanding, basic and dilutive, the effect of dilutive options and the number of options which are not dilutive because the average price of the Company's common stock was less than the exercise prices. The treasury stock method was used to measure the effect of the dilution. Three months ended September 30, Nine months ended September 30, (In thousands) 2021 2020 2021 2020 Weighted average common stock outstanding-Basic 23,692 23,353 23,619 23,329 Effect of dilutive options 4 — 2 1 Weighted average common stock outstanding-Diluted 23,696 23,353 23,621 23,330 Non-dilutive options 1,350 1,516 1,474 1,418 Years non-dilutive options were issued 2014 through 2020 2011 through 2020 2011 and 2014 through 2020 2014 through 2020

Stock-based Employee Compensa_2

Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Disclosure of Share-based Compensation Arrangements by Share-based Payment Award	Directors Officers Grant date April 24, 2020 May 7, 2021 April 24, 2020 May 7, 2021 Exercise price $ 50.00 $ 43.89 $ 50.00 $ 43.89 Volatility 0.258 0.297 0.240 0.275 Expected life (years) 5.0 5.0 7.0 7.0 Assumed yield 3.80 % 4.96 % 3.85 % 4.97 % Risk-free rate 0.36 % 0.77 % 0.51 % 1.24 %
Summary of Option Activity	The table below summarizes the option activity for the nine months ended September 30, 2021: Number of Weighted Aggregate Outstanding at January 1 1,502,670 $ 52.86 $ — Granted 250,500 43.89 — Exercised (3,000) 41.82 3,450 Expired/Forfeited (87,000) 53.60 — Outstanding at September 30 1,663,170 51.49 171,250 Exercisable at September 30 1,137,295 52.89 133,340

Business Segments (Tables)

Business Segments (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Business Segments	(In thousands) Shopping Mixed-Use Corporate Consolidated Three months ended September 30, 2021 Real estate rental operations: Revenue $ 42,485 $ 17,771 $ — $ 60,256 Expenses (8,640) (6,724) — (15,364) Income from real estate 33,845 11,047 — 44,892 Interest expense, net and amortization of deferred debt costs — — (10,914) (10,914) Depreciation and amortization of lease costs (7,203) (5,264) — (12,467) General and administrative — — (4,626) (4,626) Net income (loss) $ 26,642 $ 5,783 $ (15,540) $ 16,885 Capital investment $ 2,629 $ 8,722 $ — $ 11,351 Total assets $ 960,247 $ 766,761 $ 12,492 $ 1,739,500 Three months ended September 30, 2020 Real estate rental operations: Revenue $ 40,336 $ 16,424 $ — $ 56,760 Expenses (8,755) (6,184) — (14,939) Income from real estate 31,581 10,240 — 41,821 Interest expense, net and amortization of deferred debt costs — — (12,398) (12,398) Depreciation and amortization of lease costs (8,169) (5,544) — (13,713) General and administrative — — (4,107) (4,107) Net income (loss) $ 23,412 $ 4,696 $ (16,505) $ 11,603 Capital investment $ 2,733 $ 6,703 $ — $ 9,436 Total assets $ 982,381 $ 643,395 $ 55,598 $ 1,681,374 (In thousands) Shopping Mixed-Use Corporate Consolidated Nine Months Ended September 30, 2021 Real estate rental operations: Revenue $ 126,935 $ 52,050 $ — $ 178,985 Expenses (27,087) (19,454) — (46,541) Income from real estate 99,848 32,596 — 132,444 Interest expense, net and amortization of deferred debt costs — — (34,559) (34,559) Depreciation and amortization of deferred leasing costs (21,639) (16,213) — (37,852) General and administrative — — (14,234) (14,234) Net income (loss) $ 78,209 $ 16,383 $ (48,793) $ 45,799 Capital investment $ 8,200 $ 30,631 $ — $ 38,831 Total assets $ 960,247 $ 766,761 $ 12,492 $ 1,739,500 Nine Months Ended September 30, 2020 Real estate rental operations: Revenue $ 120,236 $ 46,687 $ — $ 166,923 Expenses (26,041) (16,848) — (42,889) Income from real estate 94,195 29,839 — 124,034 Interest expense, net and amortization of deferred debt costs — — (34,011) (34,011) Depreciation and amortization of deferred leasing costs (22,812) (14,781) — (37,593) General and administrative — — (13,790) (13,790) Net income (loss) $ 71,383 $ 15,058 $ (47,801) $ 38,640 Capital investment $ 11,622 $ 36,741 $ — $ 48,363 Total assets $ 982,381 $ 643,395 $ 55,598 $ 1,681,374

Organization, Formation and Str

Organization, Formation and Structure (Details)	9 Months Ended
	Sep. 30, 2021propertystore
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of shopping centers | store	33
Saul Holdings Limited Partnership
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Percentage of ownership in operating partnership	73.40%
Giant Food
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of shopping centers | store	11
Giant Food | Revenue | Customer Concentration Risk
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Percentage of total revenue	5.30%
No Individual Tenant | Revenue | Customer Concentration Risk
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Percentage of total revenue	2.50%
Shopping Centers
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of real estate properties	50
Mixed-Use Properties
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of real estate properties	7
Non-operating Development Properties
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of real estate properties	4

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Narrative (Details) $ in Millions	Sep. 30, 2021USD ($)
Accounting Policies [Abstract]
Accrued rent	$ 4.6
Deferred rent receivables, net	$ 4.5

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for doubtful accounts	$ (3,512)	$ (5,223)
Total	61,855	64,917
Rents currently due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for doubtful accounts	7,576	13,321
Deferred rents
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for doubtful accounts	5,388	8,205
Straight-line rent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for doubtful accounts	46,429	44,863
Other receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, before allowance for doubtful accounts	$ 5,974	$ 3,751

Real Estate Transactions - Narr

Real Estate Transactions - Narrative (Details)	Sep. 30, 2021USD ($)shares	Jun. 29, 2021USD ($)shares	Nov. 05, 2019ashares	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Mar. 05, 2021USD ($)a	Dec. 31, 2020USD ($)	Jan. 01, 2019leaseExtensionOption
Real Estate [Line Items]
Assets placed in service	$ 2,266,362,000			$ 2,266,362,000			$ 2,124,796,000
Lease renewal term								5 years
Right-of-use asset	321,900			321,900
Operating lease liability	334,500			334,500
Deferred leasing costs, net	24,638,000			24,638,000			26,872,000
Accumulated amortization deferred leasing cost	$ 47,700,000			47,700,000			$ 44,500,000
Depreciation expense				34,200,000	$ 33,600,000
Repairs and maintenance expense				10,200,000	8,000,000
Impairment of real estate				$ 0
Business acquisition, expenses reimbursed						$ 7,400,000
Operating lease, incremental borrowing rate				5.63%
Finance lease, right-of-use asset, amortization				$ 104,000
Finance lease, interest expense				$ 362,800
Contribution Agreement
Real Estate [Line Items]
Right-of-use asset						19,400,000
Operating lease liability						19,400,000
Number of partnership units issued in transaction (in shares) | shares			1,416,071
Business acquisition, transaction costs						$ 1,200,000
Leasehold Interest Contributed In Contribution Agreement
Real Estate [Line Items]
Number of partnership units issued in transaction (in shares) | shares	469,740
Asset acquisition consideration transferred		$ 21,500,000
Payments to acquire businesses, gross		$ 700,000
Leasehold Interest Contributed In Contribution Agreement | Limited Partner
Real Estate [Line Items]
Number of partnership units issued in transaction (in shares) | shares		469,740
BF Saul Real Estate Investment Trust | Contribution Agreement
Real Estate [Line Items]
Area of land | a			10.3
Minimum
Real Estate [Line Items]
Operating lease term of contract	1 year			1 year
Maximum
Real Estate [Line Items]
Operating lease term of contract	15 years			15 years
Building | Minimum
Real Estate [Line Items]
Estimated useful life				35 years
Building | Maximum
Real Estate [Line Items]
Estimated useful life				50 years
Building Improvements | Maximum
Real Estate [Line Items]
Estimated useful life				20 years
Lease Acquisition Costs
Real Estate [Line Items]
Amortization of intangible assets				$ 3,600,000	$ 4,000,000
The Waycroft and Ashbrook Marketplace
Real Estate [Line Items]
Assets placed in service	$ 8,700,000			$ 8,700,000
Corporate Headquarters
Real Estate [Line Items]
Number of options to extend lease | leaseExtensionOption								1
Twinbrook Metro Station | BF Saul Real Estate Investment Trust | Contribution Agreement
Real Estate [Line Items]
Area of land | a			6.8			6.8
Twinbrook Metro Station Leasehold Interest | BF Saul Real Estate Investment Trust | Contribution Agreement
Real Estate [Line Items]
Area of land | a			1.3			1.3

Real Estate - Schedule of Const

Real Estate - Schedule of Construction in Progress (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Real Estate [Line Items]
Construction in progress	$ 191,707	$ 69,477
Twinbrook Quarter
Real Estate [Line Items]
Construction in progress	127,348	0
Hampden House
Real Estate [Line Items]
Construction in progress	53,619	50,723
The Waycroft
Real Estate [Line Items]
Construction in progress	0	8,651
Ashbrook Marketplace
Real Estate [Line Items]
Construction in progress	0	153
Other
Real Estate [Line Items]
Construction in progress	$ 10,740	$ 9,950

Noncontrolling Interests - Ho_2

Noncontrolling Interests - Holders of Convertible Limited Partnership Units in the Operating Partnership (Details)	Sep. 30, 2021shares	Sep. 30, 2021shares	Sep. 30, 2020shares	Sep. 30, 2021shares	Sep. 30, 2020shares
Noncontrolling Interest [Line Items]
Limited partnership units (in shares)	8,100,000	8,100,000		8,100,000
Leasehold Interest Contributed In Contribution Agreement
Noncontrolling Interest [Line Items]
Number of partnership units issued in transaction (in shares)	469,740
Saul Holdings Limited Partnership
Noncontrolling Interest [Line Items]
Percentage of ownership interest of noncontrolling interest	25.10%	25.10%		25.10%
Third Party Investor
Noncontrolling Interest [Line Items]
Percentage of ownership interest of noncontrolling interest	1.50%	1.50%		1.50%
Noncontrolling Interests
Noncontrolling Interest [Line Items]
Limited partnership units, conversion ratio	1	1		1
Outstanding stock percent that should be acquired for rights to be exercised	39.90%	39.90%		39.90%
Limited partnership units convertible into shares of common stock, eligible for conversion	1,000,000	1,000,000		1,000,000
Fully converted partnership units and diluted weighted average shares outstanding		33,700,000	31,300,000	32,900,000	31,200,000
Partners capital account units placed In escrow				700,000
Noncontrolling Interests | Saul Holdings Limited Partnership
Noncontrolling Interest [Line Items]
Percentage of ownership interest of noncontrolling interest	26.60%	26.60%		26.60%
Limited partnership units, conversion ratio	1	1		1

Notes Payable, Revolving Cred_3

Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs - Narrative (Details) - USD ($)	Sep. 30, 2021	Aug. 31, 2021	Jun. 11, 2021	Jan. 05, 2021	Oct. 01, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Principal amount	$ 1,147,511,000					$ 1,200,000,000
Debt outstanding with fixed-rate	949,500,000					980,800,000
Debt outstanding with variable-rate	198,000,000					179,500,000
Carrying value of properties collateralizing mortgage notes	1,100,000,000					1,200,000,000
Outstanding line of credit	95,028,000					103,913,000
Notes payable	794,586,000					827,603,000
Principal amount	1,135,935,000
Unamortized deferred debt costs	11,576,000					9,300,000
Debt issuance costs amortization	$ 7,200,000					8,700,000
Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 525,000,000
Mortgages | Jamestown Place
Debt Instrument [Line Items]
Payment for debt extinguishment or debt prepayment cost				$ 6,100,000
Mortgages | Hunt Club Corners
Debt Instrument [Line Items]
Payment for debt extinguishment or debt prepayment cost			$ 5,000,000
Revolving Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate spread on LIBOR	1.40%
Revolving Credit Facility | LIBOR | Minimum
Debt Instrument [Line Items]
Interest rate spread on LIBOR		1.35%
Revolving Credit Facility | LIBOR | Maximum
Debt Instrument [Line Items]
Interest rate spread on LIBOR		1.95%
Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 425,000,000
Term Facility | LIBOR
Debt Instrument [Line Items]
Interest rate spread on LIBOR	1.35%
Term Facility | LIBOR | Minimum
Debt Instrument [Line Items]
Interest rate spread on LIBOR		1.30%
Term Facility | LIBOR | Maximum
Debt Instrument [Line Items]
Interest rate spread on LIBOR		1.90%
Term Facility | Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 100,000,000
Unsecured Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, remaining borrowing capacity	$ 228,200,000
Outstanding line of credit	98,000,000					$ 104,500,000
Letter of Credit
Debt Instrument [Line Items]
Outstanding line of credit	185,000
Park Van Ness Loan
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure	3,300,000
Notes payable	65,100,000
Park Van Ness Loan | Subsequent Event
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure					$ 0
Broadlands Village Mortgage
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure	3,700,000
Principal amount	29,900,000
Avenel Business Park
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure	6,300,000
Avenel Business Park | Mortgages
Debt Instrument [Line Items]
Principal amount	24,400,000
The Waycroft Mortgage
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure	23,600,000
The Waycroft Mortgage | Mortgages
Debt Instrument [Line Items]
Principal amount	148,500,000
Ashbrook Marketplace Mortgage | Mortgages
Debt Instrument [Line Items]
Principal amount	21,500,000
Kentlands Place Mortgage | Mortgages
Debt Instrument [Line Items]
Principal amount	$ 29,200,000

Notes Payable, Revolving Cred_4

Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs - Scheduled Maturities of Debt, Including Scheduled Principal Amortization (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Balloon Payments
October 1 through December 31, 2021	$ 0
2022	36,502
2023	9,225
2024	66,164
2025	118,363
2026	134,088
Thereafter	537,673
Principal amount	902,015
Scheduled Principal Amortization
October 1 through December 31, 2021	7,679
2022	31,016
2022	31,479
2023	30,876
2024	27,860
2025	24,333
Thereafter	92,253
Principal amount	245,496
Total
October 1 through December 31, 2021	7,679
2022	67,518
2023	40,704
2024	97,040
2025	146,223
2026	158,421
Thereafter	629,926
Principal amount	1,147,511	$ 1,200,000
Unamortized deferred debt costs	11,576	9,300
Net	1,135,935
Outstanding line of credit	95,028	103,913
Unsecured Revolving Credit Facility
Total
Outstanding line of credit	$ 98,000	$ 104,500

Notes Payable, Revolving Cred_5

Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs - Interest Expense and Amortization of Deferred Debt Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Disclosure [Abstract]
Interest incurred	$ 12,481	$ 12,933	$ 38,062	$ 38,788
Amortization of deferred debt costs	425	402	1,237	1,163
Capitalized interest	(1,991)	(909)	(4,734)	(5,813)
Interest expense	10,915	12,426	34,565	34,138
Less: Interest income	1	28	6	127
Interest expense, net and amortization of deferred debt costs	$ 10,914	$ 12,398	$ 34,559	$ 34,011

Equity - Narrative (Details)

Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Class of Stock [Line Items]
Income attributable to noncontrolling interests	$ (3,747)	$ (2,236)	$ (9,653)	$ (7,681)
Series D Cumulative Redeemable Preferred Stock
Class of Stock [Line Items]
Depositary shares outstanding	3		3
Depository shares to cumulative redeemable preferred stock ratio			1.00%
Percentage of redeemable preferred stock			6.125%
Cumulative redeemable preferred stock liquidation preference (in usd per share)	$ 25		$ 25
Annual dividend on depositary shares (in usd per share)			$ 1.53125
Series E Cumulative Redeemable Preferred Stock
Class of Stock [Line Items]
Depositary shares outstanding	4.4		4.4
Depository shares to cumulative redeemable preferred stock ratio			1.00%
Percentage of redeemable preferred stock			6.00%
Cumulative redeemable preferred stock liquidation preference (in usd per share)	$ 25		$ 25
Annual dividend on depositary shares (in usd per share)			$ 1.50

Equity - Per Share Data (Detail

Equity - Per Share Data (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Class of Stock [Line Items]
Weighted average common stock outstanding-Basic (in shares)	23,692	23,353	23,619	23,329
Effect of dilutive options (in shares)	4	0	2	1
Weighted average common stock outstanding-Diluted (in shares)	23,696	23,353	23,621	23,330
Non-dilutive options
Class of Stock [Line Items]
Non-dilutive options (in shares)	1,350	1,516	1,474	1,418

Related Party Transactions (Det

Related Party Transactions (Details)	Jun. 30, 2021shares	May 09, 2018shares	Aug. 31, 2016a	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Mar. 05, 2021a	Dec. 31, 2020USD ($)	Nov. 05, 2019a
Related Party Transaction [Line Items]
Company contribution to a multi employer 401K plan at discretionary amount of employee's cash compensation, maximum percentage				6.00%
Company contribution to a multi employer 401K plan at discretionary amount of employee's cash compensation, amount				$ 328,500	$ 255,200
Deferred compensation, employee contribution				2.00%
Deferred compensation, company contribution				$ 120,800	$ 164,800
Deferred compensation, company contribution percentage				3	3
Deferred compensation, cumulative unfunded liability				$ 3,000,000			$ 2,900,000
Ancillary costs and expenses				5,900,000	$ 6,000,000
Liability due to The Saul Organization for the Company's share of these ancillary costs and expenses				$ 883,900			$ 782,700
Percentage of annual increase in base rent				3.00%
Rent expense				$ 611,200	609,200
Insurance commissions and fees expense				$ 280,700	$ 320,300
BF Saul Real Estate Investment Trust | Contribution Agreement
Related Party Transaction [Line Items]
Area of land | a								10.3
Twinbrook Metro Station | BF Saul Real Estate Investment Trust | Contribution Agreement
Related Party Transaction [Line Items]
Area of land | a						6.8		6.8
Twinbrook Metro Station Leasehold Interest | BF Saul Real Estate Investment Trust | Contribution Agreement
Related Party Transaction [Line Items]
Area of land | a						1.3		1.3
Ashbrook Marketplace | BF Saul Real Estate Investment Trust
Related Party Transaction [Line Items]
Area of real estate acquired | a			13.7
Limited partnership units issued for purchase (in shares) | shares	93,674	176,680

Stock-based Employee Compensa_3

Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors - Narrative (Details) - USD ($)	Jun. 30, 2021	May 07, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation (in shares)	118,183								7,429
Shares due to exercise of employee stock options and issuance of directors' deferred stock			743,000	6,038,000	910	984,000	3,109,000	11,745
Granted (in shares)									250,500
Stock option expense									$ 1,000,000
Future expense			$ 2,000,000						2,000,000
Exercised									$ 3,450	$ 85,268
Closing share price (in usd per share)			$ 44.06						$ 44.06
Share-based compensation arrangement by share-based payment award, options, grants since inception			1,397,625						1,397,625
Weighted average remaining contractual life of the Company's outstanding options									6 years 3 months 18 days
Weighted average remaining contractual life of the Company's exercisable options									5 years 3 months 18 days
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares due to exercise of employee stock options and issuance of directors' deferred stock									7,874
Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		250,500
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period									10 years
Employee Stock Option | Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period									4 years

Stock-based Employee Compensa_4

Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors - Stock Options Issued (Details)	May 07, 2021$ / shares	Apr. 24, 2020$ / shares	Sep. 30, 2021$ / shares
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Exercise price (in usd per share)			$ 41.82
Directors
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Exercise price (in usd per share)	$ 43.89	$ 50
Volatility	0.297	0.258
Expected life (years)	5 years	5 years
Assumed yield	4.96%	3.80%
Risk-free rate	0.77%	0.36%
Officers
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Exercise price (in usd per share)	$ 43.89	$ 50
Volatility	0.275	0.240
Expected life (years)	7 years	7 years
Assumed yield	4.97%	3.85%
Risk-free rate	1.24%	0.51%

Stock-based Employee Compensa_5

Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors - Summary of Option Activity (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Number of Shares
Outstanding at beginning of period (in shares)	1,502,670
Granted (in shares)	250,500
Exercised (in shares)	(3,000)
Expired/Forfeited (in shares)	(87,000)
Outstanding at end of period (in shares)	1,663,170
Exercisable at end of period (in shares)	1,137,295
Weighted Average Exercise Price per share
Outstanding at beginning of period (in usd per share)	$ 52.86
Granted (in usd per share)	43.89
Exercised (in usd per share)	41.82
Expired/Forfeited (in usd per share)	53.60
Outstanding at end of period (in usd per share)	51.49
Exercisable at end of period (in usd per share)	$ 52.89
Aggregate Intrinsic Value
Outstanding at beginning of period	$ 0
Granted	0
Exercised	3,450	$ 85,268
Expired/Forfeited	0
Outstanding at end of period	171,250
Exercisable at end of period	$ 133,340

Fair Value of Financial Instr_2

Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Notes payable, fixed interest rate	3.60%	3.40%
Notes payable, aggregate fair value	$ 937.3	$ 981
Notes payable, principal balance	$ 949.5	$ 980.8

Business Segments - Narrative (

Business Segments - Narrative (Details)	9 Months Ended
	Sep. 30, 2021segment
Segment Reporting [Abstract]
Number of reportable business segments	2

Business Segments - Schedule of

Business Segments - Schedule of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Real estate rental operations:
Revenue	$ 60,256			$ 56,760			$ 178,985	$ 166,923
Expenses	(15,364)			(14,939)			(46,541)	(42,889)
Income from real estate	44,892			41,821			132,444	124,034
Interest expense, net and amortization of deferred debt costs	(10,914)			(12,398)			(34,559)	(34,011)
Depreciation and amortization of lease costs	(12,467)			(13,713)			(37,852)	(37,593)
General and administrative	(4,626)			(4,107)			(14,234)	(13,790)
Net Income	16,885	$ 16,119	$ 12,795	11,603	$ 10,208	$ 16,829	45,799	38,640
Capital investment	11,351			9,436			38,831	48,363
Total assets	1,739,500			1,681,374			1,739,500	1,681,374	$ 1,645,572
Operating Segments | Shopping Centers
Real estate rental operations:
Revenue	42,485			40,336			126,935	120,236
Expenses	(8,640)			(8,755)			(27,087)	(26,041)
Income from real estate	33,845			31,581			99,848	94,195
Interest expense, net and amortization of deferred debt costs	0			0			0	0
Depreciation and amortization of lease costs	(7,203)			(8,169)			(21,639)	(22,812)
General and administrative	0			0			0	0
Net Income	26,642			23,412			78,209	71,383
Capital investment	2,629			2,733			8,200	11,622
Total assets	960,247			982,381			960,247	982,381
Operating Segments | Mixed-Use Properties
Real estate rental operations:
Revenue	17,771			16,424			52,050	46,687
Expenses	(6,724)			(6,184)			(19,454)	(16,848)
Income from real estate	11,047			10,240			32,596	29,839
Interest expense, net and amortization of deferred debt costs	0			0			0	0
Depreciation and amortization of lease costs	(5,264)			(5,544)			(16,213)	(14,781)
General and administrative	0			0			0	0
Net Income	5,783			4,696			16,383	15,058
Capital investment	8,722			6,703			30,631	36,741
Total assets	766,761			643,395			766,761	643,395
Corporate and Other
Real estate rental operations:
Revenue	0			0			0	0
Expenses	0			0			0	0
Income from real estate	0			0			0	0
Interest expense, net and amortization of deferred debt costs	(10,914)			(12,398)			(34,559)	(34,011)
Depreciation and amortization of lease costs	0			0			0	0
General and administrative	(4,626)			(4,107)			(14,234)	(13,790)
Net Income	(15,540)			(16,505)			(48,793)	(47,801)
Capital investment	0			0			0	0
Total assets	$ 12,492			$ 55,598			$ 12,492	$ 55,598

Impact of COVID-19 - Narrative

Impact of COVID-19 - Narrative (Details) $ in Millions	Sep. 30, 2021USD ($)
Unusual or Infrequent Items, or Both [Abstract]
Accrued rent	$ 4.6
Deferred rent receivables, net	$ 4.5