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Transactions with Related Parties (Details) - Affiliated Entity - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Washington Housing Initiative
Related Party Transaction [Line Items]
Total capital commitments	$ 114,400,000		$ 114,400,000
Commitment	11,200,000		11,200,000
Remaining commitment	8,300,000		8,300,000
Supervisory Services of Properties \| BMS
Related Party Transaction [Line Items]
Related party transaction amount	4,100,000	$ 3,300,000	8,500,000	$ 8,600,000
Fees from Legacy JBG Funds and Washington Housing Initiative \| Legacy JBG Funds and Washington Housing Initiative
Related Party Transaction [Line Items]
Revenue from related parties	5,800,000	4,700,000	11,600,000	12,700,000
Receivables	2,800,000		2,800,000		$ 7,500,000
Office Rent \| Unconsolidated Real Estate Ventures
Related Party Transaction [Line Items]
Revenue from related parties	$ 495,000	$ 2,400,000	$ 766,000	$ 3,700,000