Real Estate - Additional Information (Detail)			12 Months Ended
	Jun. 29, 2021 USD ($)	Mar. 15, 2021 USD ($)	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) shares	Mar. 05, 2021 USD ($)	Nov. 05, 2019 a
Real Estate Properties [Line Items]
Lessee, operating lease, incremental borrowing rate			5.63%
Finance lease, right-of-use asset, amortization					$ 104,000
Finance lease, interest expense					362,800
Below market lease, carrying amount			$ 23,300,000	$ 23,300,000
Below market lease, accumulated amortization			18,600,000	17,300,000
Accretion income, intangible liabilities			1,300,000	1,300,000	1,400,000
Leasehold Interest Contributed In Contribution Agreement
Real Estate Properties [Line Items]
Asset acquisition, consideration transferred	$ 21,500,000
Payments to acquire businesses, gross	$ 700,000
Lease acquisition costs
Real Estate Properties [Line Items]
Intangible assets gross carrying amount			10,600,000	10,700,000
Intangible assets, accumulated amortization			9,400,000	9,200,000
Amortization expense			$ 300,000	400,000	500,000
Weighted-average amortization period			4 years 8 months 12 days
Above Market Leases
Real Estate Properties [Line Items]
Intangible assets gross carrying amount			$ 600,000	600,000
Intangible assets, accumulated amortization			227,700	194,800
Amortization expense			$ 32,900	$ 32,900	$ 32,900
Weighted-average amortization period			5 years 9 months 18 days
Below Market Leases
Real Estate Properties [Line Items]
Weighted-average amortization period			5 years
Contribution Agreement
Real Estate Properties [Line Items]
Business acquisition, transaction costs						$ 1,200,000
Right-of-use asset obtained in exchange for finance lease liability		$ 19,400,000
Finance lease, liability						19,400,000
Contribution Agreement | BF Saul Real Estate Investment Trust
Real Estate Properties [Line Items]
Area of land | a							10.3
Twinbrook Metro Station
Real Estate Properties [Line Items]
Stock issued during period, shares, acquisitions | shares					469,740,000
Twinbrook Metro Station | Restricted Stock Units (RSUs)
Real Estate Properties [Line Items]
Stock issued during period, shares, acquisitions | shares			1,416,071,000		1,416,071,000
Twinbrook Metro Station | Contribution Agreement | BF Saul Real Estate Investment Trust
Real Estate Properties [Line Items]
Area of land | a							6.8
Twinbrook Metro Station Leasehold Interest | Contribution Agreement | BF Saul Real Estate Investment Trust
Real Estate Properties [Line Items]
Area of land | a							1.3
Twinbrook Quarter
Real Estate Properties [Line Items]
Business acquisition, expenses reimbursed						$ 7,400,000