Ancillary Costs and Expenses

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- Definition

Deferred Compensation Arrangement with Individual, Contributions by Plan Participants, Percentage of Salary, Maximum

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- Definition

Deferred Compensation Arrangement with Individual, Employer Contribution, Percentage Deferred Compensation

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- Definition

Real Estate, Equity Interests Issued Or Issuable, Value Assigned

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- Definition

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

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- Definition

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

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- Definition

Related Party Transaction, Area of Real Estate Acquired

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Related Party Transactions, Automatic Renewal Period

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- Definition

Area of land held.

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- Definition

Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement.

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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

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- Definition

The number of shares issued as [noncash or part noncash] consideration for a business or asset acquired. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

Insurance and claims costs directly related to goods produced and sold, or services rendered, during the reporting period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Related Party Transactions - Additional Information (Detail)				1 Months Ended		12 Months Ended
	Nov. 05, 2019 USD ($) a $ / shares shares	May 09, 2018 shares	Dec. 08, 2016	May 31, 2018 a shares	Aug. 31, 2016 a	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Related Party Transaction [Line Items]
Company contribution to a multi employer 401K plan at discretionary amount of employee's cash compensation, maximum percentage						6.00%
Company contribution to a multi employer 401K plan at discretionary amount of employee's cash compensation, amount						$ 322,200	$ 345,900	$ 349,500
Deferred compensation, employee contribution, percentage						2.00%
Deferred compensation, employer contribution, percentage						3	3	3
Deferred compensation, company contribution, amount						$ 345,200	$ 282,500	$ 228,500
Deferred compensation, cumulative unfunded liability						3,100,000	2,700,000
Ancillary costs and expenses						8,400,000	8,400,000	8,100,000
Liability due to the Saul Organization for the company's share of these ancillary costs and expenses						918,700	933,400
Automatic renewal period			12 months
Insurance commissions and fees expense						$ 399,600	$ 407,900	$ 288,400
Contribution Agreement
Related Party Transaction [Line Items]
Number of partnership units issued in transaction (in shares) \| shares	1,416,071
Value of units issued (in dollars per share) \| $ / shares	$ 56.00
Value assigned to units issued	$ 79,300,000
BF Saul Real Estate Investment Trust \| Ashbrook Marketplace
Related Party Transaction [Line Items]
Area of real estate property (in square feet) \| a					13.7
Ashbrook Marketplace \| BF Saul Real Estate Investment Trust
Related Party Transaction [Line Items]
Area of land \| a				13.7
Limited partnership units issued (in shares) \| shares		176,680		176,680
Land Contributed in Contribution Agreement \| BF Saul Real Estate Investment Trust
Related Party Transaction [Line Items]
Area of land \| a	6.8
Leasehold Interest Contributed in Contribution Agreement \| BF Saul Real Estate Investment Trust
Related Party Transaction [Line Items]
Area of land \| a	1.3