Qualified Affordable Housing Project Investments, Total Capital Commitments

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

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Amount of transactions with related party during the financial reporting period.

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Transactions with Related Parties (Details) - Affiliated Entity - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Washington Housing Initiative
Related Party Transaction [Line Items]
Total capital commitments	$ 114,400,000
Commitment	11,200,000
Supervisory Services of Properties \| BMS
Related Party Transaction [Line Items]
Related party transaction amount	4,300,000	$ 5,300,000
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	8,000,000.0
Receivables	7,900,000		$ 7,500,000
Office Rent \| Unconsolidated Real Estate Ventures
Related Party Transaction [Line Items]
Related party transaction amount	$ 271,000	$ 1,300,000