Long-Term Debt, Balloon Payments

No definition available.

Name:	bfs_LongTermDebtBalloonPayments
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-Term Debt, Maturities, Balloon Payments after Year Five

No definition available.

Name:	bfs_LongTermDebtMaturitiesBalloonPaymentsAfterYearFive
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-Term Debt, Maturities, Balloon Payments in Next Twelve Months

No definition available.

Name:	bfs_LongTermDebtMaturitiesBalloonPaymentsInNextTwelveMonths
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-Term Debt, Maturities, Repayments of Principal and Balloon Payments [Abstract]

No definition available.

Name:	bfs_LongTermDebtMaturitiesRepaymentsOfPrincipalAndBalloonPaymentsAbstract
Namespace Prefix:	bfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Long-Term Debt, Maturities, Repayments of Principal and Balloon Payments after Year Five

No definition available.

Name:	bfs_LongTermDebtMaturitiesRepaymentsOfPrincipalAndBalloonPaymentsAfterYearFive
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-Term Debt, Maturities, Repayments of Principal and Balloon Payments in Next Twelve Months

No definition available.

Name:	bfs_LongTermDebtMaturitiesRepaymentsOfPrincipalAndBalloonPaymentsInNextTwelveMonths
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Maturities, Balloon Payments [Abstract]

No definition available.

Name:	bfs_LongtermDebtMaturitiesBalloonPaymentsAbstract
Namespace Prefix:	bfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Long-term Debt, Maturities, Balloon Payments in Year Five

No definition available.

Name:	bfs_LongtermDebtMaturitiesBalloonPaymentsInYearFive
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Maturities, Balloon Payments in Year Three

No definition available.

Name:	bfs_LongtermDebtMaturitiesBalloonPaymentsInYearThree
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Maturities, Balloon Payments in Year Two

No definition available.

Name:	bfs_LongtermDebtMaturitiesBalloonPaymentsInYearTwo
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt Maturities Balloon Payments in Year Four

No definition available.

Name:	bfs_LongtermDebtMaturitiesBalloonPaymentsinYearFour
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Five

No definition available.

Name:	bfs_LongtermDebtMaturitiesRepaymentsOfPrincipalAndBalloonPaymentsInYearFive
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Four

No definition available.

Name:	bfs_LongtermDebtMaturitiesRepaymentsOfPrincipalAndBalloonPaymentsInYearFour
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Three

No definition available.

Name:	bfs_LongtermDebtMaturitiesRepaymentsOfPrincipalAndBalloonPaymentsInYearThree
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Two

No definition available.

Name:	bfs_LongtermDebtMaturitiesRepaymentsOfPrincipalAndBalloonPaymentsInYearTwo
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt, Repayments of Principal and Balloon Payments

No definition available.

Name:	bfs_LongtermDebtRepaymentsOfPrincipalAndBalloonPayments
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Repayments of Principal and Balloon Payments, Net of Debt Issuance Costs

No definition available.

Name:	bfs_LongtermRepaymentsofPrincipalandBalloonPaymentsNetofDebtIssuanceCosts
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482925/835-30-45-3

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Name:	us-gaap_DeferredFinanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69C

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1D

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-4

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_LongTermDebtByMaturityAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481544/470-10-50-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Name:	us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481544/470-10-50-1

Name:	us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481544/470-10-50-1

Name:	us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481544/470-10-50-1

Name:	us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481544/470-10-50-1

Name:	us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481544/470-10-50-1