Preferred Stock, Base Redemption Price Per Share

No definition available.

Name:	bfs_PreferredStockBaseRedemptionPricePerShare
Namespace Prefix:	bfs_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Real Estate, Equity Interests Issued Or Issuable, Value Assigned

+ References

No definition available.

+ Details

Name:	bfs_RealEstateEquityInterestsIssuedOrIssuableValueAssigned
Namespace Prefix:	bfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Real Estate, Equity Interests Issued Or Issuable, Value Assigned Per Share

+ References

No definition available.

+ Details

Name:	bfs_RealEstateEquityInterestsIssuedOrIssuableValueAssignedPerShare
Namespace Prefix:	bfs_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Real Estate, Equity Interests Issued or Issuable, Number of Shares

+ References

No definition available.

+ Details

Name:	bfs_RealEstateEquityInterestsIssuedorIssuableNumberofShares
Namespace Prefix:	bfs_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Area of land held.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfLand
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21488-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21564-112644

+ Details

Name:	us-gaap_PreferredStockRedemptionPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_StatementClassOfStockAxis=bfs_SeriesCCumulativePreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=bfs_BFSaulRealEstateInvestmentTrustMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=bfs_LandContributedInContributionAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=bfs_LeaseholdInterestContributedInContributionAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=bfs_ContributionAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events - Narrative (Details) - Subsequent Event $ / shares in Units, $ in Millions	Nov. 05, 2019 USD ($) a $ / shares shares	Oct. 17, 2019 $ / shares
Series C Cumulative Redeemable Preferred Stock
Subsequent Event [Line Items]
Preferred stock gross redemption price (in dollars per share)		$ 25.00
Preferred stock net redemption price (in dollars per share)		$ 25.07638
BF Saul Real Estate Investment Trust \| Land Contributed In Contribution Agreement
Subsequent Event [Line Items]
Area of land \| a	6.8
BF Saul Real Estate Investment Trust \| Leasehold Interest Contributed In Contribution Agreement
Subsequent Event [Line Items]
Area of land \| a	1.3
Contribution Agreement
Subsequent Event [Line Items]
Number of partnership units issued in transaction (in shares) \| shares	1,416,071
Value of units issued (in dollars per share)	$ 56.00
Value assigned to units issued \| $	$ 79.3