XML 19 R48.htm IDEA: XBRL DOCUMENT v2.4.1.9
Mortgage Notes Payable, Revolving Credit Facility, Interest Expense and Amortization of Deferred Debt Costs - Additional Information (Detail) (USD $)
12 Months Ended 0 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Apr. 26, 2012
Feb. 27, 2013
Apr. 10, 2013
Apr. 11, 2012
Mar. 19, 2013
May 28, 2013
Sep. 04, 2013
Oct. 25, 2013
Jun. 24, 2014
Debt Instrument [Line Items]                        
Outstanding debt $ 857,400,000us-gaap_SecuredDebtOther                      
Fixed rate mortgages 808,997,000us-gaap_SecuredDebt 820,068,000us-gaap_SecuredDebt                    
Debt outstanding 857,388,000bfs_LongTermDebtRepaymentsOfPrincipalAndBalloonPayments 820,100,000bfs_LongTermDebtRepaymentsOfPrincipalAndBalloonPayments                    
Debt outstanding with fixed-rate   789,900,000us-gaap_LongtermDebtPercentageBearingFixedInterestAmount                    
Debt outstanding with variable-rate   30,200,000us-gaap_LongtermDebtPercentageBearingVariableInterestAmount                    
Line of credit facility, maximum borrowing capacity 231,600,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity                      
Outstanding line of credit 43,000,000us-gaap_LineOfCredit 0us-gaap_LineOfCredit                    
Letter of credit facility 448,000bfs_LetterOfCreditFacilitiesMaximumBorrowingCapacity                      
Guarantor obligations, maximum exposure 51,000,000us-gaap_GuaranteeObligationsMaximumExposure 51,000,000us-gaap_GuaranteeObligationsMaximumExposure                    
Debt instrument maturity term 8 years 8 months 21 days [1]                      
Defeased mortgage loan 22,071,000us-gaap_RepaymentsOfSecuredDebt 71,308,000us-gaap_RepaymentsOfSecuredDebt 117,595,000us-gaap_RepaymentsOfSecuredDebt                  
Proceeds from debt 0us-gaap_ProceedsFromIssuanceOfSecuredDebt [2] 101,600,000us-gaap_ProceedsFromIssuanceOfSecuredDebt 83,500,000us-gaap_ProceedsFromIssuanceOfSecuredDebt                  
Debt instrument fixed interest rate 3.65%us-gaap_DebtInstrumentInterestRateEffectivePercentage 4.85%us-gaap_DebtInstrumentInterestRateEffectivePercentage                    
Capitalization of debt issuance cost 1,300,000us-gaap_DeferredFinanceCostsGross 3,200,000us-gaap_DeferredFinanceCostsGross 2,200,000us-gaap_DeferredFinanceCostsGross                  
White Oak Shopping Center                        
Debt Instrument [Line Items]                        
Debt instrument amount       10,500,000us-gaap_DebtInstrumentFaceAmount
/ bfs_RealEstatePropertyNameAxis
= bfs_WhiteOakShoppingCenterMember
               
Debt instrument fixed interest rate       8.11%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ bfs_RealEstatePropertyNameAxis
= bfs_WhiteOakShoppingCenterMember
               
Principal amortization period       25 years                
Debt instrument required final principal payment       18,500,000bfs_DebtInstrumentFinalPaymentAmount
/ bfs_RealEstatePropertyNameAxis
= bfs_WhiteOakShoppingCenterMember
               
Blended fixed interest rate       7.00%bfs_SecuredDebtInstrumentWeightedAverageInterestRate
/ bfs_RealEstatePropertyNameAxis
= bfs_WhiteOakShoppingCenterMember
               
Metro Pike Center                        
Debt Instrument [Line Items]                        
Debt instrument amount         15,600,000us-gaap_DebtInstrumentFaceAmount
/ bfs_RealEstatePropertyNameAxis
= bfs_MetroPikeCenterMember
             
Debt instrument, maturity year         2016              
Principal amortization period         25 years              
Debt instrument required final principal payment         14,800,000bfs_DebtInstrumentFinalPaymentAmount
/ bfs_RealEstatePropertyNameAxis
= bfs_MetroPikeCenterMember
             
Debt instrument, term         3 years              
Interest rate spread on LIBOR         1.65%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ bfs_RealEstatePropertyNameAxis
= bfs_MetroPikeCenterMember
             
Existing loan extension period         2 years              
Repayment of debt         15,900,000us-gaap_RepaymentsOfLongTermDebt
/ bfs_RealEstatePropertyNameAxis
= bfs_MetroPikeCenterMember
             
Northrock                        
Debt Instrument [Line Items]                        
Debt instrument amount         15,000,000us-gaap_DebtInstrumentFaceAmount
/ bfs_RealEstatePropertyNameAxis
= bfs_NorthrockMember
             
Debt instrument, maturity year         2016              
Principal amortization period         25 years              
Debt instrument required final principal payment         14,200,000bfs_DebtInstrumentFinalPaymentAmount
/ bfs_RealEstatePropertyNameAxis
= bfs_NorthrockMember
             
Debt instrument, term         3 years              
Interest rate spread on LIBOR         1.65%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ bfs_RealEstatePropertyNameAxis
= bfs_NorthrockMember
             
Existing loan extension period         2 years              
Repayment of debt         15,000,000us-gaap_RepaymentsOfLongTermDebt
/ bfs_RealEstatePropertyNameAxis
= bfs_NorthrockMember
             
Cruse Market Place                        
Debt Instrument [Line Items]                        
Repayment of debt           6,900,000us-gaap_RepaymentsOfLongTermDebt
/ bfs_RealEstatePropertyNameAxis
= bfs_CruseMarketPlaceMember
           
Northrock Loan                        
Debt Instrument [Line Items]                        
Guarantor obligations, maximum exposure 7,500,000us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_LongtermDebtTypeAxis
= bfs_NorthrockLoanMember
                     
5.84% due May 2027 | Seven Corners Shopping Center                        
Debt Instrument [Line Items]                        
Debt instrument maturity term             15 years          
Debt instrument amount             73,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
         
Debt instrument, maturity year             2027          
Debt instrument fixed interest rate             5.84%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
         
Principal amortization period             25 years          
Defeased mortgage loan             63,000,000us-gaap_RepaymentsOfSecuredDebt
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
         
Proceeds from debt             10,000,000us-gaap_ProceedsFromIssuanceOfSecuredDebt
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
         
4.04% due April 2028 | Hampshire Langley                        
Debt Instrument [Line Items]                        
Debt instrument amount               18,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_HampshireLangleyMember
       
Debt instrument, maturity year               2028        
Debt instrument fixed interest rate               4.04%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_HampshireLangleyMember
       
Debt instrument required periodic principal and interest payment               95,400us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_HampshireLangleyMember
       
Debt instrument required final principal payment               9,500,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_HampshireLangleyMember
       
Debt instrument, term               15 years        
3.51% due June 2028 | Beacon Center                        
Debt Instrument [Line Items]                        
Debt instrument amount                 35,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_BeaconCenterMember
     
Debt instrument, maturity year                 2028      
Debt instrument fixed interest rate                 3.51%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_BeaconCenterMember
     
Debt instrument required periodic principal and interest payment                 203,200us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_BeaconCenterMember
     
Principal amortization period                 20 years      
Debt instrument required final principal payment                 11,400,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_BeaconCenterMember
     
Debt instrument, term                 15 years      
3.99% due September 2028 | Seabreeze Plaza                        
Debt Instrument [Line Items]                        
Debt instrument amount                   18,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
   
Debt instrument, maturity year                   2028    
Debt instrument fixed interest rate                   3.99%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
   
Debt instrument, term                   15 years    
Repayment of debt                   13,500,000us-gaap_RepaymentsOfLongTermDebt
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
   
Payments of debt extinguishment costs                   497,000us-gaap_PaymentsOfDebtExtinguishmentCosts
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
   
4.88% due September 2032 | Park Van Ness                        
Debt Instrument [Line Items]                        
Debt instrument fixed interest rate                     4.88%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointEightEightMaturingSeptemberTwentyThirtyTwoMember
/ bfs_RealEstatePropertyNameAxis
= bfs_ParkVanNessMember
 
Principal amortization period                     25 years  
Unsecured Revolving Credit Facility                        
Debt Instrument [Line Items]                        
Line of credit facility, maximum borrowing capacity                       275,000,000.0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= bfs_UnsecuredRevolvingCreditFacilityMember
Extension in line of credit facility period 1 year                     1 year
Line of credit facility maturity date                       Jun. 23, 2018
Description of variable rate basis                       one-month LIBOR
Fixed Rate Mortgage Notes Payable                        
Debt Instrument [Line Items]                        
Fixed rate mortgages 784,757,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
789,872,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
                   
Debt instrument maturity term 9 years 3 months 0 days [1]                      
Debt instrument fixed interest rate 5.70%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
[1]                      
Fixed Rate Mortgage Notes Payable | White Oak Shopping Center                        
Debt Instrument [Line Items]                        
Debt instrument fixed interest rate       4.90%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ bfs_RealEstatePropertyNameAxis
= bfs_WhiteOakShoppingCenterMember
               
Fixed Rate Mortgage Notes Payable | Metro Pike Center bank loan                        
Debt Instrument [Line Items]                        
Guarantor obligations, maximum exposure 7,800,000us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_MetroPikeCenterBankLoanMember
                     
Fixed Rate Mortgage Notes Payable | 5.84% due May 2027                        
Debt Instrument [Line Items]                        
Fixed rate mortgages 69,397,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
[3] 70,856,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
                   
Debt instrument fixed interest rate 5.84%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
                     
Fixed Rate Mortgage Notes Payable | 5.84% due May 2027 | Seven Corners Shopping Center                        
Debt Instrument [Line Items]                        
Debt instrument amount 73,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
                     
Debt instrument required periodic principal and interest payment 463,200us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
          463,200us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
         
Principal amortization period 25 years                      
Debt instrument required final principal payment 42,300,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
          42,300,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FivePointEightFourMaturingMayTwentyTwentySevenMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SevenCornersMember
         
Fixed Rate Mortgage Notes Payable | 4.04% due April 2028                        
Debt Instrument [Line Items]                        
Fixed rate mortgages 17,281,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
[4] 17,718,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
                   
Debt instrument fixed interest rate 4.04%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
                     
Fixed Rate Mortgage Notes Payable | 4.04% due April 2028 | Hampshire Langley                        
Debt Instrument [Line Items]                        
Debt instrument required periodic principal and interest payment 95,400us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_HampshireLangleyMember
                     
Principal amortization period 25 years                      
Debt instrument required final principal payment 9,500,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointZeroFourMaturingAprilTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_HampshireLangleyMember
                     
Fixed Rate Mortgage Notes Payable | 3.51% due June 2028                        
Debt Instrument [Line Items]                        
Fixed rate mortgages 33,140,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
[5] 34,391,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
                   
Debt instrument fixed interest rate 3.51%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
                     
Fixed Rate Mortgage Notes Payable | 3.51% due June 2028 | Beacon Center                        
Debt Instrument [Line Items]                        
Debt instrument required periodic principal and interest payment 203,200us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_BeaconCenterMember
                     
Principal amortization period 20 years                      
Debt instrument required final principal payment 11,400,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointFiveOneMaturingJuneTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_BeaconCenterMember
                     
Fixed Rate Mortgage Notes Payable | 3.99% due September 2028                        
Debt Instrument [Line Items]                        
Fixed rate mortgages 17,462,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
[6] 17,895,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
                   
Debt instrument fixed interest rate 3.99%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
                     
Fixed Rate Mortgage Notes Payable | 3.99% due September 2028 | Seabreeze Plaza                        
Debt Instrument [Line Items]                        
Debt instrument required periodic principal and interest payment 94,900us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
                94,900us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
   
Principal amortization period 25 years                 25 years    
Debt instrument required final principal payment 9,500,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
                9,500,000bfs_DebtInstrumentFinalPaymentAmount
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_ThreePointNineNineMaturingSeptemberTwentyTwentyEightMember
/ bfs_RealEstatePropertyNameAxis
= bfs_SeabreezePlazaMember
   
Fixed Rate Mortgage Notes Payable | 4.88% due September 2032                        
Debt Instrument [Line Items]                        
Fixed rate mortgages 5,391,000us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointEightEightMaturingSeptemberTwentyThirtyTwoMember
[7] 0us-gaap_SecuredDebt
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
= bfs_FourPointEightEightMaturingSeptemberTwentyThirtyTwoMember
                   
Debt instrument fixed interest rate 4.88%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_DebtInstrumentAxis
= bfs_FixedRateMortgageNotesPayableMember
/ us-gaap_LongtermDebtTypeAxis
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Fixed Rate Mortgage Notes Payable | 4.88% due September 2032 | Park Van Ness                        
Debt Instrument [Line Items]                        
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Debt instrument required periodic principal and interest payment 413,500us-gaap_DebtInstrumentPeriodicPayment
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Principal amortization period 25 years                      
Debt instrument required final principal payment 39,600,000bfs_DebtInstrumentFinalPaymentAmount
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Variable Rate Loans Payable                        
Debt Instrument [Line Items]                        
Variable rate loans 72,631,000us-gaap_LoansPayable
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30,196,000us-gaap_LoansPayable
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Debt instrument maturity term 2 years 5 months 18 days [1]                      
Interest rate spread on LIBOR 1.53159%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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Variable Rate Loans Payable | Northrock Loan                        
Debt Instrument [Line Items]                        
Variable rate loans 14,525,000us-gaap_LoansPayable
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[8] 14,802,000us-gaap_LoansPayable
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Variable Rate Loans Payable | Northrock Loan | Northrock                        
Debt Instrument [Line Items]                        
Debt instrument required periodic principal and interest payment 47,000us-gaap_DebtInstrumentPeriodicPayment
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Debt instrument required final principal payment 14,200,000bfs_DebtInstrumentFinalPaymentAmount
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Variable Rate Loans Payable | Metro Pike Center bank loan                        
Debt Instrument [Line Items]                        
Variable rate loans 15,106,000us-gaap_LoansPayable
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Variable Rate Loans Payable | Metro Pike Center bank loan | Metro Pike Center                        
Debt Instrument [Line Items]                        
Debt instrument required periodic principal and interest payment 48,000us-gaap_DebtInstrumentPeriodicPayment
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Debt instrument required final principal payment 14,800,000bfs_DebtInstrumentFinalPaymentAmount
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LIBOR                        
Debt Instrument [Line Items]                        
Interest rate basis points 1.45%bfs_LineOfCreditFacilityInterestRateBasisPoints
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Debt Covenant [Member]                        
Debt Instrument [Line Items]                        
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907,200,000us-gaap_PledgedAssetsNotSeparatelyReportedRealEstate
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Debt covenant, percentage of net proceeds of additional equity issuance 80.00%bfs_DebtInstrumentPercentageOfNetProceedsOfAdditionalEquityIssuance
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Credit agreement leverage ratio 60.00%bfs_CreditAgreementLeverageRatio
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Interest coverage ratio required minimum 2.0bfs_InterestCoverageRatioRequiredMinimum
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Required fixed charge coverage ratio 1.3bfs_RequiredFixedChargeCoverageRatio
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Minimum | Unsecured Revolving Credit Facility                        
Debt Instrument [Line Items]                        
Interest rate spread on LIBOR                       1.45%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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Debt Instrument [Line Items]                        
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Debt Instrument [Line Items]                        
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Maximum | Unsecured Revolving Credit Facility                        
Debt Instrument [Line Items]                        
Interest rate spread on LIBOR                       2.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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[1] Interest rate and scheduled maturity data presented as of December 31, 2014. Totals computed using weighted averages.
[2] The 2014 acquisition of real estate and proceeds from notes payable each exclude $11,000 in connection with the sale and leaseback of the Company's Olney property.
[3] The loan in the original amount of $73.0 million closed in May 2012, is collateralized by Seven Corners and requires equal monthly principal and interest payments of $463,200 based upon a 25-year amortization schedule and a final payment of $42.3 million at loan maturity. Principal of $1.5 million was amortized during 2014.
[4] The loan is collateralized by Hampshire Langley and requires equal monthly principal and interest payments of $95,400 based upon a 25 -year amortization schedule and a final payment of $9.5 million at loan maturity. Principal of $437,000 was amortized in 2014.
[5] The loan is collateralized by Beacon Center and requires equal monthly principal and interest payments of $203,200 based upon a 20-year amortization schedule and a final payment of $11.4 million at loan maturity. Principal of $1,251,000 was amortized in 2014.
[6] The loan is collateralized by Seabreeze Plaza and requires equal monthly principal and interest payments of $94,900 based upon a 25-year amortization schedule and a final payment of $9.5 million at loan maturity. Principal of $433,000 was amortized in 2014.
[7] The loan is a $71.6 million construction-to-permanent facility that is collateralized by and will finance a portion of the construction costs of Park Van Ness. During the construction period, interest will be funded by the loan. After conversion to a permanent loan, monthly principal and interest payments totaling $413,500 will be required based upon a 25-year amortization schedule. A final payment of $39.6 million will be due at maturity.
[8] The loan is collateralized by Northrock and requires monthly principal and interest payments of approximately $47,000 and a final payment of $14.2 million at maturity. Principal of $277,000 was amortized during 2014.
[9] The loan is collateralized by Metro Pike Center and requires monthly principal and interest payments of approximately $48,000 and a final payment of $14.8 million at loan maturity. Principal of $288,000 was amortized during 2014.