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

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Qualified Affordable Housing Project Investments, Total Capital Commitments

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount of commitment and contingent commitment, including amount of delayed equity contribution, for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, commitment and contingent commitment related to investment under tax credit program not meeting condition for accounting under proportional amortization method.

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Amount of transactions with related party during the financial 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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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Transactions with Related Parties (Details) - USD ($)	1 Months Ended	12 Months Ended
Transactions with Related Parties (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Transactions with Related Parties
Revenues		$ 547,312,000	$ 604,198,000	$ 605,824,000
Receivables		13,483,000	$ 30,895,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| 4747 Bethesda Avenue
Transactions with Related Parties
Percentage of ownership interest in assets sold	80.00%		80.00%
Related party \| Washington Housing Initiative
Transactions with Related Parties
Completed capital commitments		114,400,000
Commitment		11,200,000
Remaining unfunded commitment		2,900,000
Related party \| Fee-based real estate services \| JBG Legacy Funds and Washington Housing Initiative Impact Pool and its Affiliates
Transactions with Related Parties
Revenues		13,000,000	$ 21,300,000	20,000,000
Receivables		2,100,000	3,500,000
Related party \| Office Rent \| Unconsolidated Real Estate Ventures
Transactions with Related Parties
Related party payments		5,400,000	5,000,000	922,000
Related party \| Supervisory Services of Properties \| BMS
Transactions with Related Parties
Related party payments		$ 9,500,000	$ 9,300,000	$ 10,700,000