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Real Estate and Accumulated Depreciation (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Real Estate Properties [Line Items]
Initial Basis	$ 805,178bfs_RealEstateInvestmentPropertyCostInitialBasis
Cost Capitalized Subsequent to Acquisition	730,226bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition
Basis at Close of Period, Land	423,052us-gaap_LandAndLandImprovements
Basis at Close of Period, Building and Improvements	1,135,286us-gaap_BuildingsAndImprovementsGross
Basis at Close of Period, Leasehold Interests	1,821us-gaap_RealEstateInvestmentsOther
Total	1,560,159us-gaap_RealEstateInvestmentPropertyAtCost		1,459,439us-gaap_RealEstateInvestmentPropertyAtCost	1,466,068us-gaap_RealEstateInvestmentPropertyAtCost	1,417,845us-gaap_RealEstateInvestmentPropertyAtCost
Accumulated Depreciation	396,617us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation		364,663us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation	353,305us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation	326,397us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation
Book Value	1,163,542us-gaap_RealEstateInvestmentPropertyNet		1,094,776us-gaap_RealEstateInvestmentPropertyNet
Related Debt	808,997us-gaap_SecuredDebt		820,068us-gaap_SecuredDebt
Development Land, Related Debt	5,391us-gaap_ConstructionLoan		0us-gaap_ConstructionLoan
Total, Related Debt	814,388bfs_SecuredDebtIncludingConstructionLoan
Shopping Centers
Real Estate Properties [Line Items]
Initial Basis	750,377bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Cost Capitalized Subsequent to Acquisition	394,340bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Basis at Close of Period, Land	384,569us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Basis at Close of Period, Building and Improvements	758,327us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Basis at Close of Period, Leasehold Interests	1,821us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Total	1,144,717us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Accumulated Depreciation	270,400us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Book Value	874,317us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Related Debt	631,228us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember
Shopping Centers | Ashburn Village, Ashburn, VA
Real Estate Properties [Line Items]
Initial Basis	11,431bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Cost Capitalized Subsequent to Acquisition	19,492bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Basis at Close of Period, Land	6,764us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Basis at Close of Period, Building and Improvements	24,159us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Total	30,923us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Accumulated Depreciation	10,868us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Book Value	20,055us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Related Debt	30,253us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyOneMember
Date Acquired	1994-03
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Ashburn Village, Ashburn, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	1994
Shopping Centers | Ashburn Village, Ashburn, VA | Construction One | Minimum
Real Estate Properties [Line Items]
Date of Construction	2000
Shopping Centers | Ashburn Village, Ashburn, VA | Construction One | Maximum
Real Estate Properties [Line Items]
Date of Construction	2006
Shopping Centers | Ashland Square Phase I, Dumfries, VA
Real Estate Properties [Line Items]
Initial Basis	1,178bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Cost Capitalized Subsequent to Acquisition	7,503bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Basis at Close of Period, Land	1,178us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Basis at Close of Period, Building and Improvements	7,503us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Total	8,681us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Accumulated Depreciation	776us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Book Value	7,905us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwoMember
Date Acquired	2004-12
Shopping Centers | Ashland Square Phase I, Dumfries, VA | Minimum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	20 years
Shopping Centers | Ashland Square Phase I, Dumfries, VA | Maximum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Ashland Square Phase I, Dumfries, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	2007
Shopping Centers | Ashland Square Phase I, Dumfries, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	2013
Shopping Centers | Beacon Center, Alexandria, VA
Real Estate Properties [Line Items]
Initial Basis	1,493bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Cost Capitalized Subsequent to Acquisition	18,232bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Basis at Close of Period, Land	0us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Basis at Close of Period, Building and Improvements	18,631us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Basis at Close of Period, Leasehold Interests	1,094us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Total	19,725us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Accumulated Depreciation	12,707us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Book Value	7,018us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Related Debt	33,140us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThreeMember
Date Acquired	1972-01
Shopping Centers | Beacon Center, Alexandria, VA | Minimum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Beacon Center, Alexandria, VA | Maximum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Beacon Center, Alexandria, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	1960
Shopping Centers | Beacon Center, Alexandria, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1974
Shopping Centers | BJ’s Wholesale Club, Alexandria, VA
Real Estate Properties [Line Items]
Initial Basis	22,623bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Cost Capitalized Subsequent to Acquisition	0bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Basis at Close of Period, Land	22,623us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Basis at Close of Period, Building and Improvements	0us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Total	22,623us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Accumulated Depreciation	0us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Book Value	22,623us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Related Debt	11,587us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourMember
Date Acquired	2008-03
Buildings and Improvements Depreciable Lives in Years	0 years
Shopping Centers | Boca Valley Plaza, Boca Raton, FL
Real Estate Properties [Line Items]
Initial Basis	16,720bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Cost Capitalized Subsequent to Acquisition	1,297bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Basis at Close of Period, Land	5,735us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Basis at Close of Period, Building and Improvements	12,282us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Total	18,017us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Accumulated Depreciation	3,478us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Book Value	14,539us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Related Debt	10,881us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiveMember
Date Acquired	2004-02
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Boulevard, Fairfax, VA
Real Estate Properties [Line Items]
Initial Basis	4,883bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Cost Capitalized Subsequent to Acquisition	4,487bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Basis at Close of Period, Land	3,687us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Basis at Close of Period, Building and Improvements	5,683us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Total	9,370us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Accumulated Depreciation	2,194us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Book Value	7,176us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Related Debt	9,239us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixMember
Date Acquired	1994-04
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Boulevard, Fairfax, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	1969
Shopping Centers | Boulevard, Fairfax, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1999
Shopping Centers | Boulevard, Fairfax, VA | Construction Three
Real Estate Properties [Line Items]
Date of Construction	2009
Shopping Centers | Briggs Chaney MarketPlace, Silver Spring, MD
Real Estate Properties [Line Items]
Initial Basis	27,037bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Cost Capitalized Subsequent to Acquisition	2,957bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Basis at Close of Period, Land	9,789us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Basis at Close of Period, Building and Improvements	20,205us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Total	29,994us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Accumulated Depreciation	6,076us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Book Value	23,918us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Related Debt	15,761us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySevenMember
Date Acquired	2004-04
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Broadlands Village, Ashburn, VA
Real Estate Properties [Line Items]
Initial Basis	5,316bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Cost Capitalized Subsequent to Acquisition	25,285bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Basis at Close of Period, Land	5,300us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Basis at Close of Period, Building and Improvements	25,301us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Total	30,601us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Accumulated Depreciation	8,354us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Book Value	22,247us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Related Debt	18,826us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEightMember
Date Acquired	2002-03
Shopping Centers | Broadlands Village, Ashburn, VA | Minimum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Broadlands Village, Ashburn, VA | Maximum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Broadlands Village, Ashburn, VA | Construction One | Minimum
Real Estate Properties [Line Items]
Date of Construction	2002
Shopping Centers | Broadlands Village, Ashburn, VA | Construction One | Maximum
Real Estate Properties [Line Items]
Date of Construction	2003
Shopping Centers | Broadlands Village, Ashburn, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	2004
Shopping Centers | Broadlands Village, Ashburn, VA | Construction Three
Real Estate Properties [Line Items]
Date of Construction	2006
Shopping Centers | Countryside Marketplace, Sterling, VA
Real Estate Properties [Line Items]
Initial Basis	28,912bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Cost Capitalized Subsequent to Acquisition	3,039bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Basis at Close of Period, Land	7,666us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Basis at Close of Period, Building and Improvements	24,285us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Total	31,951us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Accumulated Depreciation	6,538us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Book Value	25,413us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Related Debt	15,819us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineMember
Date Acquired	2004-02
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Cranberry Square, Westminster, MD
Real Estate Properties [Line Items]
Initial Basis	31,578bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Cost Capitalized Subsequent to Acquisition	464bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Basis at Close of Period, Land	6,700us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Basis at Close of Period, Building and Improvements	25,342us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Total	32,042us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Accumulated Depreciation	2,061us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Book Value	29,981us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Related Debt	18,645us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTenMember
Date Acquired	2011-09
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Cruse MarketPlace, Cumming, GA
Real Estate Properties [Line Items]
Initial Basis	12,226bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Cost Capitalized Subsequent to Acquisition	198bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Basis at Close of Period, Land	3,920us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Basis at Close of Period, Building and Improvements	8,504us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Total	12,424us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Accumulated Depreciation	2,350us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Book Value	10,074us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyElevenMember
Date Acquired	2004-03
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Flagship Center, Rockville, MD
Real Estate Properties [Line Items]
Initial Basis	160bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Cost Capitalized Subsequent to Acquisition	9bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Basis at Close of Period, Land	169us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Basis at Close of Period, Building and Improvements	0us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Total	169us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Accumulated Depreciation	0us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Book Value	169us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwelveMember
Date of Construction	1972
Date Acquired	1972-01
Buildings and Improvements Depreciable Lives in Years	0 years
Shopping Centers | French Market, Oklahoma City, OK
Real Estate Properties [Line Items]
Initial Basis	5,781bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Cost Capitalized Subsequent to Acquisition	13,782bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Basis at Close of Period, Land	1,118us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Basis at Close of Period, Building and Improvements	18,445us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Total	19,563us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Accumulated Depreciation	9,444us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Book Value	10,119us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirteenMember
Date Acquired	1974-03
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | French Market, Oklahoma City, OK | Construction One
Real Estate Properties [Line Items]
Date of Construction	1972
Shopping Centers | French Market, Oklahoma City, OK | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1998
Shopping Centers | Germantown, Germantown, MD
Real Estate Properties [Line Items]
Initial Basis	3,576bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Cost Capitalized Subsequent to Acquisition	743bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Basis at Close of Period, Land	2,034us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Basis at Close of Period, Building and Improvements	2,285us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Total	4,319us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Accumulated Depreciation	1,385us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Book Value	2,934us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFourteenMember
Date of Construction	1990
Date Acquired	1993-08
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | 750/730 N. Glebe Road, Arlington, VA
Real Estate Properties [Line Items]
Initial Basis	42,313bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Cost Capitalized Subsequent to Acquisition	13bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Basis at Close of Period, Land	40,907us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Basis at Close of Period, Building and Improvements	1,419us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Total	42,326us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Accumulated Depreciation	160us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Book Value	42,166us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_A750730NorthGlebeArlingtonVAMember
Shopping Centers | 750/730 N. Glebe Road, Arlington, VA | Acquisition Date One
Real Estate Properties [Line Items]
Date Acquired	2014-08
Buildings and Improvements Depreciable Lives in Years	3 years
Shopping Centers | 750/730 N. Glebe Road, Arlington, VA | Acquisition Date Two
Real Estate Properties [Line Items]
Date Acquired	2014-12
Buildings and Improvements Depreciable Lives in Years	2 years
Shopping Centers | The Glen, Woodbridge, VA
Real Estate Properties [Line Items]
Initial Basis	12,918bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Cost Capitalized Subsequent to Acquisition	7,536bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Basis at Close of Period, Land	5,299us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Basis at Close of Period, Building and Improvements	15,155us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Total	20,454us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Accumulated Depreciation	7,327us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Book Value	13,127us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Related Debt	9,045us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySixteenMember
Date Acquired	1994-06
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | The Glen, Woodbridge, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	1993
Shopping Centers | The Glen, Woodbridge, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	2005
Shopping Centers | Great Eastern, District Heights, MD
Real Estate Properties [Line Items]
Initial Basis	4,993bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Cost Capitalized Subsequent to Acquisition	10,669bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Basis at Close of Period, Land	3,785us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Basis at Close of Period, Building and Improvements	11,877us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Total	15,662us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Accumulated Depreciation	7,726us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Book Value	7,936us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertySeventeenMember
Date Acquired	1972-01
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Great Eastern, District Heights, MD | Construction One
Real Estate Properties [Line Items]
Date of Construction	1958
Shopping Centers | Great Eastern, District Heights, MD | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1960
Shopping Centers | Great Falls Center, Great Falls, VA
Real Estate Properties [Line Items]
Initial Basis	41,750bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Cost Capitalized Subsequent to Acquisition	2,350bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Basis at Close of Period, Land	14,766us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Basis at Close of Period, Building and Improvements	29,334us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Total	44,100us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Accumulated Depreciation	4,988us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Book Value	39,112us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Related Debt	14,909us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyEighteenMember
Date Acquired	2008-03
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Hampshire Langley, Takoma, MD
Real Estate Properties [Line Items]
Initial Basis	3,159bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Cost Capitalized Subsequent to Acquisition	3,338bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Basis at Close of Period, Land	1,856us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Basis at Close of Period, Building and Improvements	4,641us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Total	6,497us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Accumulated Depreciation	3,351us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Book Value	3,146us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Related Debt	17,281us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyNineteenMember
Date of Construction	1960
Date Acquired	1972-01
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Hunt Club Corners, Apopka, FL
Real Estate Properties [Line Items]
Initial Basis	12,584bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Cost Capitalized Subsequent to Acquisition	3,115bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Basis at Close of Period, Land	4,822us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Basis at Close of Period, Building and Improvements	10,877us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Total	15,699us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Accumulated Depreciation	2,555us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Book Value	13,144us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Related Debt	6,100us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyMember
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Hunt Club Corners, Apopka, FL | Acquisition Date One
Real Estate Properties [Line Items]
Date Acquired	2006-06
Shopping Centers | Hunt Club Corners, Apopka, FL | Acquisition Date Two
Real Estate Properties [Line Items]
Date Acquired	2012-12
Shopping Centers | Jamestown Place, Altamonte Springs, FL
Real Estate Properties [Line Items]
Initial Basis	14,055bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Cost Capitalized Subsequent to Acquisition	960bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Basis at Close of Period, Land	4,455us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Basis at Close of Period, Building and Improvements	10,560us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Total	15,015us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Accumulated Depreciation	2,532us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Book Value	12,483us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Related Debt	8,346us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyOneMember
Date Acquired	2005-11
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Kentlands Square I, Gaithersburg, MD
Real Estate Properties [Line Items]
Initial Basis	14,379bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Cost Capitalized Subsequent to Acquisition	177bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Basis at Close of Period, Land	5,006us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Basis at Close of Period, Building and Improvements	9,550us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Total	14,556us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Accumulated Depreciation	2,958us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Book Value	11,598us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Related Debt	7,527us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyTwoMember
Date of Construction	2002
Date Acquired	2002-09
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Kentlands Square II, Gaithersburg, MD
Real Estate Properties [Line Items]
Initial Basis	76,723bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Cost Capitalized Subsequent to Acquisition	954bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Basis at Close of Period, Land	22,800us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Basis at Close of Period, Building and Improvements	54,877us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Total	77,677us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Accumulated Depreciation	4,387us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Book Value	73,290us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Related Debt	39,932us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyThreeMember
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Kentlands Square II, Gaithersburg, MD | Acquisition Date One
Real Estate Properties [Line Items]
Date Acquired	2011-09
Shopping Centers | Kentlands Square II, Gaithersburg, MD | Acquisition Date Two
Real Estate Properties [Line Items]
Date Acquired	2013-09
Shopping Centers | Kentlands Place, Gaithersburg, MD
Real Estate Properties [Line Items]
Initial Basis	1,425bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Cost Capitalized Subsequent to Acquisition	7,163bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Basis at Close of Period, Land	1,425us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Basis at Close of Period, Building and Improvements	7,163us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Total	8,588us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Accumulated Depreciation	2,863us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Book Value	5,725us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFourMember
Date of Construction	2005
Date Acquired	2004-01
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Lansdowne Town Center, Leesburg, VA
Real Estate Properties [Line Items]
Initial Basis	6,545bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Cost Capitalized Subsequent to Acquisition	36,313bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Basis at Close of Period, Land	6,546us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Basis at Close of Period, Building and Improvements	36,312us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Total	42,858us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Accumulated Depreciation	10,174us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Book Value	32,684us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Related Debt	35,222us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyFiveMember
Date of Construction	2006
Date Acquired	2002-11
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Leesburg Pike Plaza, Baileys Crossroads, VA
Real Estate Properties [Line Items]
Initial Basis	2,418bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Cost Capitalized Subsequent to Acquisition	6,173bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Basis at Close of Period, Land	1,132us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Basis at Close of Period, Building and Improvements	7,459us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Total	8,591us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Accumulated Depreciation	5,582us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Book Value	3,009us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Related Debt	16,750us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySixMember
Date of Construction	1965
Date Acquired	1966-02
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Lumberton Plaza, Lumberton, NJ
Real Estate Properties [Line Items]
Initial Basis	4,400bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Cost Capitalized Subsequent to Acquisition	11,160bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Basis at Close of Period, Land	950us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Basis at Close of Period, Building and Improvements	14,610us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Total	15,560us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Accumulated Depreciation	11,676us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Book Value	3,884us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentySevenMember
Date of Construction	1975
Date Acquired	1975-12
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Metro Pike Center, Rockville, MD
Real Estate Properties [Line Items]
Initial Basis	33,123bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Cost Capitalized Subsequent to Acquisition	2,069bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Basis at Close of Period, Land	26,064us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Basis at Close of Period, Building and Improvements	9,128us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Total	35,192us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Accumulated Depreciation	771us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Book Value	34,421us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Related Debt	15,106us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyEightMember
Date Acquired	2010-12
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Shops at Monocacy, Frederick, MD
Real Estate Properties [Line Items]
Initial Basis	9,541bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Cost Capitalized Subsequent to Acquisition	14,002bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Basis at Close of Period, Land	9,260us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Basis at Close of Period, Building and Improvements	14,283us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Total	23,543us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Accumulated Depreciation	4,320us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Book Value	19,223us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Related Debt	14,014us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyTwentyNineMember
Date Acquired	2003-11
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Shops at Monocacy, Frederick, MD | Construction One | Minimum
Real Estate Properties [Line Items]
Date of Construction	2003
Shopping Centers | Shops at Monocacy, Frederick, MD | Construction One | Maximum
Real Estate Properties [Line Items]
Date of Construction	2004
Shopping Centers | Northrock, Warrenton, VA
Real Estate Properties [Line Items]
Initial Basis	12,686bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Cost Capitalized Subsequent to Acquisition	14,981bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Basis at Close of Period, Land	12,686us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Basis at Close of Period, Building and Improvements	14,981us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Total	27,667us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Accumulated Depreciation	2,283us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Book Value	25,384us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Related Debt	14,525us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyMember
Date of Construction	2009
Date Acquired	2008-01
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Olde Forte Village, Ft. Washington, MD
Real Estate Properties [Line Items]
Initial Basis	15,933bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Cost Capitalized Subsequent to Acquisition	6,499bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Basis at Close of Period, Land	5,409us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Basis at Close of Period, Building and Improvements	17,023us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Total	22,432us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Accumulated Depreciation	5,583us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Book Value	16,849us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Related Debt	11,454us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyOneMember
Date Acquired	2007-03
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Olde Forte Village, Ft. Washington, MD | Construction One | Minimum
Real Estate Properties [Line Items]
Date of Construction	2003
Shopping Centers | Olde Forte Village, Ft. Washington, MD | Construction One | Maximum
Real Estate Properties [Line Items]
Date of Construction	2004
Shopping Centers | Olney, Olney, MD
Real Estate Properties [Line Items]
Initial Basis	1,884bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Cost Capitalized Subsequent to Acquisition	1,672bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Basis at Close of Period, Land	0us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Basis at Close of Period, Building and Improvements	3,556us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Total	3,556us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Accumulated Depreciation	3,180us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Book Value	376us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Related Debt	11,119us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyTwoMember
Date of Construction	1972
Date Acquired	1975-11
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Orchard Park, Dunwoody, GA
Real Estate Properties [Line Items]
Initial Basis	19,377bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Cost Capitalized Subsequent to Acquisition	781bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Basis at Close of Period, Land	7,751us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Basis at Close of Period, Building and Improvements	12,407us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Total	20,158us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Accumulated Depreciation	2,343us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Book Value	17,815us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Related Debt	10,718us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyThreeMember
Date Acquired	2007-07
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Palm Springs Center, Altamonte Springs, FL
Real Estate Properties [Line Items]
Initial Basis	18,365bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Cost Capitalized Subsequent to Acquisition	659bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Basis at Close of Period, Land	5,739us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Basis at Close of Period, Building and Improvements	13,285us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Total	19,024us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Accumulated Depreciation	3,247us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Book Value	15,777us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Related Debt	9,535us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFourMember
Date Acquired	2005-03
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Ravenwood, Baltimore, MD
Real Estate Properties [Line Items]
Initial Basis	1,245bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Cost Capitalized Subsequent to Acquisition	4,097bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Basis at Close of Period, Land	703us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Basis at Close of Period, Building and Improvements	4,639us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Total	5,342us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Accumulated Depreciation	2,602us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Book Value	2,740us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Related Debt	15,735us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyFiveMember
Date Acquired	1972-01
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Ravenwood, Baltimore, MD | Construction One
Real Estate Properties [Line Items]
Date of Construction	1959
Shopping Centers | Ravenwood, Baltimore, MD | Construction Two
Real Estate Properties [Line Items]
Date of Construction	2006
Shopping Centers | 11503 Rockville Pike/5541 Nicholson Lane, Rockville, MD
Real Estate Properties [Line Items]
Initial Basis	14,861bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Cost Capitalized Subsequent to Acquisition	11,700bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Basis at Close of Period, Land	22,113us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Basis at Close of Period, Building and Improvements	4,448us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Total	26,561us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Accumulated Depreciation	473us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Book Value	26,088us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySixMember
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | 11503 Rockville Pike/5541 Nicholson Lane, Rockville, MD | Acquisition Date One
Real Estate Properties [Line Items]
Date Acquired	2010-10
Shopping Centers | 11503 Rockville Pike/5541 Nicholson Lane, Rockville, MD | Acquisition Date Two
Real Estate Properties [Line Items]
Date Acquired	2012-12
Shopping Centers | 1500/1580/1582/1584 Rockville Pike, Rockville, MD
Real Estate Properties [Line Items]
Initial Basis	51,156bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Cost Capitalized Subsequent to Acquisition	568bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Basis at Close of Period, Land	43,863us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Basis at Close of Period, Building and Improvements	7,861us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Total	51,724us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Accumulated Depreciation	1,962us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Book Value	49,762us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtySevenMember
Date Acquired	2012-12
Shopping Centers | 1500/1580/1582/1584 Rockville Pike, Rockville, MD | Acquisition Date Two
Real Estate Properties [Line Items]
Date Acquired	2014-01
Shopping Centers | 1500/1580/1582/1584 Rockville Pike, Rockville, MD | Acquisition Date Three
Real Estate Properties [Line Items]
Date Acquired	2014-04
Shopping Centers | 1500/1580/1582/1584 Rockville Pike, Rockville, MD | Acquisition Date Four
Real Estate Properties [Line Items]
Date Acquired	2014-12
Shopping Centers | Seabreeze Plaza, Palm Harbor, FL
Real Estate Properties [Line Items]
Initial Basis	24,526bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Cost Capitalized Subsequent to Acquisition	1,391bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Basis at Close of Period, Land	8,665us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Basis at Close of Period, Building and Improvements	17,252us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Total	25,917us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Accumulated Depreciation	4,056us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Book Value	21,861us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Related Debt	17,462us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyEightMember
Date Acquired	2005-11
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Market Place at Sea Colony, Bethany Beach, DE
Real Estate Properties [Line Items]
Initial Basis	2,920bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Cost Capitalized Subsequent to Acquisition	81bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Basis at Close of Period, Land	1,147us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Basis at Close of Period, Building and Improvements	1,854us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Total	3,001us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Accumulated Depreciation	320us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Book Value	2,681us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyThirtyNineMember
Date Acquired	2008-03
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Seven Corners, Falls Church, VA
Real Estate Properties [Line Items]
Initial Basis	4,848bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Cost Capitalized Subsequent to Acquisition	43,692bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Basis at Close of Period, Land	4,913us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Basis at Close of Period, Building and Improvements	43,627us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Total	48,540us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Accumulated Depreciation	25,486us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Book Value	23,054us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Related Debt	69,397us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyMember
Date Acquired	1973-07
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Seven Corners, Falls Church, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	1956
Shopping Centers | Seven Corners, Falls Church, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1997
Shopping Centers | Severna Park Marketplace, Severna Park, MD
Real Estate Properties [Line Items]
Initial Basis	63,254bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Cost Capitalized Subsequent to Acquisition	63bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Basis at Close of Period, Land	12,700us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Basis at Close of Period, Building and Improvements	50,617us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Total	63,317us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Accumulated Depreciation	4,112us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Book Value	59,205us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Related Debt	35,125us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyOneMember
Date Acquired	2011-09
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Shops at Fairfax, Fairfax, VA
Real Estate Properties [Line Items]
Initial Basis	2,708bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Cost Capitalized Subsequent to Acquisition	9,898bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Basis at Close of Period, Land	992us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Basis at Close of Period, Building and Improvements	11,614us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Total	12,606us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Accumulated Depreciation	6,914us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Book Value	5,692us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Related Debt	6,160us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyTwoMember
Date Acquired	1975-06
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | Shops at Fairfax, Fairfax, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	1975
Shopping Centers | Shops at Fairfax, Fairfax, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1999
Shopping Centers | Smallwood Village Center, Waldorf, MD
Real Estate Properties [Line Items]
Initial Basis	17,819bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Cost Capitalized Subsequent to Acquisition	7,618bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Basis at Close of Period, Land	6,402us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Basis at Close of Period, Building and Improvements	19,035us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Total	25,437us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Accumulated Depreciation	5,025us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Book Value	20,412us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyThreeMember
Date Acquired	2006-01
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Southdale, Glen Burnie, MD
Real Estate Properties [Line Items]
Initial Basis	3,650bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Cost Capitalized Subsequent to Acquisition	20,919bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Basis at Close of Period, Land	0us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Basis at Close of Period, Building and Improvements	23,947us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Basis at Close of Period, Leasehold Interests	622us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Total	24,569us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Accumulated Depreciation	20,467us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Book Value	4,102us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFourMember
Date Acquired	1972-01
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Southdale, Glen Burnie, MD | Construction One
Real Estate Properties [Line Items]
Date of Construction	1962
Shopping Centers | Southdale, Glen Burnie, MD | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1986
Shopping Centers | Southside Plaza, Richmond, VA
Real Estate Properties [Line Items]
Initial Basis	6,728bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Cost Capitalized Subsequent to Acquisition	9,597bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Basis at Close of Period, Land	1,878us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Basis at Close of Period, Building and Improvements	14,447us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Total	16,325us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Accumulated Depreciation	11,100us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Book Value	5,225us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyFiveMember
Date of Construction	1958
Date Acquired	1972-01
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | South Dekalb Plaza, Atlanta, GA
Real Estate Properties [Line Items]
Initial Basis	2,474bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Cost Capitalized Subsequent to Acquisition	3,899bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Basis at Close of Period, Land	703us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Basis at Close of Period, Building and Improvements	5,670us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Total	6,373us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Accumulated Depreciation	4,285us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Book Value	2,088us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySixMember
Date of Construction	1970
Date Acquired	1976-02
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Thruway, Winston-Salem, NC
Real Estate Properties [Line Items]
Initial Basis	4,778bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Cost Capitalized Subsequent to Acquisition	23,157bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Basis at Close of Period, Land	5,496us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Basis at Close of Period, Building and Improvements	22,334us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Basis at Close of Period, Leasehold Interests	105us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Total	27,935us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Accumulated Depreciation	13,715us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Book Value	14,220us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Related Debt	41,441us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortySevenMember
Date Acquired	1972-05
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Thruway, Winston-Salem, NC | Construction One
Real Estate Properties [Line Items]
Date of Construction	1955
Shopping Centers | Thruway, Winston-Salem, NC | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1965
Shopping Centers | Village Center, Centreville, VA
Real Estate Properties [Line Items]
Initial Basis	16,502bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Cost Capitalized Subsequent to Acquisition	1,870bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Basis at Close of Period, Land	7,851us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Basis at Close of Period, Building and Improvements	10,521us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Total	18,372us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Accumulated Depreciation	5,713us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Book Value	12,659us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Related Debt	14,535us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyEightMember
Date of Construction	1990
Date Acquired	1993-08
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | Westview Village, Frederick, MD
Real Estate Properties [Line Items]
Initial Basis	5,146bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Cost Capitalized Subsequent to Acquisition	22,292bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Basis at Close of Period, Land	5,153us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Basis at Close of Period, Building and Improvements	22,285us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Total	27,438us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Accumulated Depreciation	4,245us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Book Value	23,193us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFortyNineMember
Date of Construction	2009
Date Acquired	2011-07
Buildings and Improvements Depreciable Lives in Years	50 years
Shopping Centers | White Oak, Silver Spring, MD
Real Estate Properties [Line Items]
Initial Basis	6,277bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Cost Capitalized Subsequent to Acquisition	5,311bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Basis at Close of Period, Land	4,649us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Basis at Close of Period, Building and Improvements	6,939us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Total	11,588us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Accumulated Depreciation	5,604us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Book Value	5,984us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Related Debt	25,639us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyMember
Date Acquired	1972-01
Buildings and Improvements Depreciable Lives in Years	40 years
Shopping Centers | White Oak, Silver Spring, MD | Construction One
Real Estate Properties [Line Items]
Date of Construction	1958
Shopping Centers | White Oak, Silver Spring, MD | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1967
Shopping Centers | Other Buildings / Improvements
Real Estate Properties [Line Items]
Cost Capitalized Subsequent to Acquisition	115bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_OtherRealEstateMember
Basis at Close of Period, Building and Improvements	115us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_OtherRealEstateMember
Total	115us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_OtherRealEstateMember
Accumulated Depreciation	84us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_OtherRealEstateMember
Book Value	31us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_OtherRealEstateMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_ShoppingCentersMember / us-gaap_RealEstatePropertiesAxis = bfs_OtherRealEstateMember
Mixed-Use Properties
Real Estate Properties [Line Items]
Initial Basis	45,179bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Cost Capitalized Subsequent to Acquisition	333,883bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Basis at Close of Period, Land	26,858us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Basis at Close of Period, Building and Improvements	352,204us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Total	379,062us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Accumulated Depreciation	126,217us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Book Value	252,845us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Related Debt	177,769us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember
Mixed-Use Properties | 1500/1580/1582/1584 Rockville Pike, Rockville, MD | Acquisition Date One
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	5 years
Mixed-Use Properties | 1500/1580/1582/1584 Rockville Pike, Rockville, MD | Acquisition Date Two
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	10 years
Mixed-Use Properties | 1500/1580/1582/1584 Rockville Pike, Rockville, MD | Acquisition Date Three
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	5 years
Mixed-Use Properties | 1500/1580/1582/1584 Rockville Pike, Rockville, MD | Acquisition Date Four
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	4 years
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD
Real Estate Properties [Line Items]
Initial Basis	21,459bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Cost Capitalized Subsequent to Acquisition	27,945bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Basis at Close of Period, Land	3,756us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Basis at Close of Period, Building and Improvements	45,648us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Total	49,404us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Accumulated Depreciation	31,663us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Book Value	17,741us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Related Debt	30,429us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyOneMember
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Minimum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	35 years
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Maximum
Real Estate Properties [Line Items]
Buildings and Improvements Depreciable Lives in Years	40 years
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Construction One
Real Estate Properties [Line Items]
Date of Construction	1984
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Construction Two
Real Estate Properties [Line Items]
Date of Construction	1986
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Construction Three
Real Estate Properties [Line Items]
Date of Construction	1990
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Construction Four
Real Estate Properties [Line Items]
Date of Construction	1998
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Construction Five
Real Estate Properties [Line Items]
Date of Construction	2000
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Acquisition Date One
Real Estate Properties [Line Items]
Date Acquired	1984-12
Mixed-Use Properties | Avenel Business Park, Gaithersburg, MD | Acquisition Date Two
Real Estate Properties [Line Items]
Date Acquired	1984-02
Mixed-Use Properties | Clarendon Center, Arlington, VA (1)
Real Estate Properties [Line Items]
Initial Basis	12,753bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Cost Capitalized Subsequent to Acquisition	185,485bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Basis at Close of Period, Land	16,287us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Basis at Close of Period, Building and Improvements	181,951us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Total	198,238us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Accumulated Depreciation	21,709us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Book Value	176,529us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Related Debt	115,291us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyTwoMember	[1]
Date of Construction	2010	[1]
Mixed-Use Properties | Clarendon Center, Arlington, VA (1) | Acquisition Date One
Real Estate Properties [Line Items]
Date Acquired	1973-07	[1]
Mixed-Use Properties | Clarendon Center, Arlington, VA (1) | Acquisition Date Two
Real Estate Properties [Line Items]
Date Acquired	1996-01	[1]
Mixed-Use Properties | Clarendon Center, Arlington, VA (1) | Acquisition Date Three
Real Estate Properties [Line Items]
Date Acquired	2002-04	[1]
Mixed-Use Properties | Crosstown Business Center, Tulsa, OK
Real Estate Properties [Line Items]
Initial Basis	3,454bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Cost Capitalized Subsequent to Acquisition	6,358bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Basis at Close of Period, Land	604us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Basis at Close of Period, Building and Improvements	9,208us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Total	9,812us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Accumulated Depreciation	6,792us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Book Value	3,020us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyThreeMember
Date of Construction	1974
Date Acquired	1975-10
Buildings and Improvements Depreciable Lives in Years	40 years
Mixed-Use Properties | 601 Pennsylvania Ave., Washington, DC
Real Estate Properties [Line Items]
Initial Basis	5,479bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Cost Capitalized Subsequent to Acquisition	62,169bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Basis at Close of Period, Land	5,667us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Basis at Close of Period, Building and Improvements	61,981us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Total	67,648us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Accumulated Depreciation	46,500us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Book Value	21,148us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Related Debt	0us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyFourMember
Date of Construction	1986
Date Acquired	1973-07
Buildings and Improvements Depreciable Lives in Years	35 years
Mixed-Use Properties | Washington Square, Alexandria, VA
Real Estate Properties [Line Items]
Initial Basis	2,034bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Cost Capitalized Subsequent to Acquisition	51,926bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Basis at Close of Period, Land	544us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Basis at Close of Period, Building and Improvements	53,416us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Total	53,960us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Accumulated Depreciation	19,553us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Book Value	34,407us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Related Debt	32,049us-gaap_SecuredDebt / us-gaap_MajorPropertyClassAxis = bfs_MixedUsePropertiesMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySixMember
Date Acquired	1973-07
Buildings and Improvements Depreciable Lives in Years	50 years
Mixed-Use Properties | Washington Square, Alexandria, VA | Construction One
Real Estate Properties [Line Items]
Date of Construction	1952
Mixed-Use Properties | Washington Square, Alexandria, VA | Construction Two
Real Estate Properties [Line Items]
Date of Construction	2000
Development Land
Real Estate Properties [Line Items]
Initial Basis	9,622bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Cost Capitalized Subsequent to Acquisition	2,003bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Basis at Close of Period, Land	11,625us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Basis at Close of Period, Building and Improvements	24,755us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Total	36,380us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Accumulated Depreciation	0us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Book Value	36,380us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Development Land, Related Debt	5,391us-gaap_ConstructionLoan / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember
Development Land | Ashland Square Phase II, Manassas, VA
Real Estate Properties [Line Items]
Initial Basis	5,292bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Cost Capitalized Subsequent to Acquisition	1,717bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Basis at Close of Period, Land	7,009us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Basis at Close of Period, Building and Improvements	0us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Total	7,009us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Accumulated Depreciation	0us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Book Value	7,009us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Development Land, Related Debt	0us-gaap_ConstructionLoan / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftySevenMember
Date Acquired	2004-12
Development Land | New Market, New Market, MD
Real Estate Properties [Line Items]
Initial Basis	2,088bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Cost Capitalized Subsequent to Acquisition	286bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Basis at Close of Period, Land	2,374us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Basis at Close of Period, Building and Improvements	0us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Total	2,374us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Accumulated Depreciation	0us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Book Value	2,374us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Development Land, Related Debt	0us-gaap_ConstructionLoan / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_RealEstatePropertyFiftyEightMember
Date Acquired	2005-09
Development Land | Park Van Ness, Washington, DC
Real Estate Properties [Line Items]
Initial Basis	2,242bfs_RealEstateInvestmentPropertyCostInitialBasis / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Cost Capitalized Subsequent to Acquisition	0bfs_RealEstateInvestmentPropertyCostCapitalizedSubsequentToAcquisition / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Basis at Close of Period, Land	2,242us-gaap_LandAndLandImprovements / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Basis at Close of Period, Building and Improvements	24,755us-gaap_BuildingsAndImprovementsGross / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Basis at Close of Period, Leasehold Interests	0us-gaap_RealEstateInvestmentsOther / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Total	26,997us-gaap_RealEstateInvestmentPropertyAtCost / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Accumulated Depreciation	0us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Book Value	26,997us-gaap_RealEstateInvestmentPropertyNet / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Development Land, Related Debt	$ 5,391us-gaap_ConstructionLoan / us-gaap_MajorPropertyClassAxis = bfs_DevelopmentLandMember / us-gaap_RealEstatePropertiesAxis = bfs_ParkVanNessMember
Development Land | Park Van Ness, Washington, DC | Development Date One
Real Estate Properties [Line Items]
Date Acquired	1973-07
Development Land | Park Van Ness, Washington, DC | Development Date Two
Real Estate Properties [Line Items]
Date Acquired	2011-02
[1] Includes the North and South Blocks and Residential

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Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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This element represents the carrying value of a short-term real estate loan to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project, usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property. Note that there are separate concepts for the current and noncurrent portions of long-term construction loans.

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Amount before accumulated deprecation and depletion of real estate held for productive use and additions or improvements to real estate held for productive use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The cumulative amount of depreciation for real estate property held for investment purposes.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Amount of real estate owned for income production and capital accretion potential, not otherwise specified in the existing taxonomy. Such real estate excludes that which is occupied or used in the business, for entertainment purposes, or held in inventory for specific purposes.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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