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 ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Washington Housing Initiative
Related Party Transaction [Line Items]
Qualified Affordable Housing Project Investments, Total Capital Commitments	$ 106.5		$ 106.5
Qualified Affordable Housing Project Investments, Commitment	10.4		10.4
Supervisory Services of Properties \| BMS
Related Party Transaction [Line Items]
Related party transaction amount	3.3	$ 5.4	8.6	$ 10.6
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	4.7	10.0	12.7	18.4
Accounts Receivable, Related Parties	8.4		8.4		$ 6.2
Office Rent \| Unconsolidated Real Estate Venture
Related Party Transaction [Line Items]
Related party transaction amount	$ 2.4	$ 1.3	$ 3.7	$ 2.5