Equity method investment summarized financial information debt.

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- Definition

Number of Properties Sold

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No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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- Definition

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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INVESTMENT IN UNCONSOLIDATED REAL ESTATE VENTURES - Schedule of Investment in Real Estate Ventures and Share of Real Estate Ventures' Income (Loss) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 20, 2024 portfolio	Nov. 30, 2024	Sep. 30, 2024	Jun. 28, 2024	Mar. 31, 2024	Dec. 21, 2020
Schedule of Equity Method Investments [Line Items]
Investments in equity securities	$ 570,455	$ 552,494
Company's unconsolidated real estate venture Income (Loss)	(191,585)	(77,915)	$ (22,016)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 757,021	1,412,758
Commerce Square Venture
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	84.00%				84.00%
Investments in equity securities	$ 179,061	272,216
Company's unconsolidated real estate venture Income (Loss)	(134,545)	(18,791)	(12,128)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 220,000	220,000
Mid-Atlantic Office JV
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	40.00%								40.00%
Investments in equity securities	$ 10,844	0
Company's unconsolidated real estate venture Income (Loss)	7,141	(26,448)	412
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 62,023	132,770
Herndon Innovation Center Metro Portfolio Venture, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	15.00%
Investments in equity securities	$ 0	3,518
Company's unconsolidated real estate venture Income (Loss)	0	(11,854)	(536)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	233,443
MAP Venture
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	5.00%							50.00%
Investments in equity securities	$ 0	(48,733)
Company's unconsolidated real estate venture Income (Loss)	(6,541)	(10,580)	(8,340)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	179,842
Cira Square
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	20.00%
Investments in equity securities	$ 42,969	25,242
Company's unconsolidated real estate venture Income (Loss)	(1,648)	(2,474)	(985)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 160,000	257,700
KB JV
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	50.00%						50.00%
Investments in equity securities	$ 42	0
Company's unconsolidated real estate venture Income (Loss)	986	0	0
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	0
Number of properties sold \| portfolio				14
4040 Wilson Venture
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	50.00%					50.00%
Investments in equity securities	$ 0	29,419
Company's unconsolidated real estate venture Income (Loss)	(10,618)	(2,536)	(1,211)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	145,000
1919 Venture
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	50.00%
Investments in equity securities	$ 0	0
Company's unconsolidated real estate venture Income (Loss)	0	0	1,392
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	0
One Uptown - Multifamily
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	50.00%
Investments in equity securities	$ 29,818	32,124
Company's unconsolidated real estate venture Income (Loss)	(3,800)	0	0
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 72,197	40,270
3025 JFK Boulevard
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	64.00%
Investments in equity securities	$ 61,379	62,034
Company's unconsolidated real estate venture Income (Loss)	(19,271)	(4,456)	(35)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 173,754	152,032
JBG 51 N Street
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	70.00%
Investments in equity securities	$ 8,209	21,150
Company's unconsolidated real estate venture Income (Loss)	(13,397)	(435)	(382)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	0
JBG 1250 First Street Office
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	70.00%
Investments in equity securities	$ 8,531	17,843
Company's unconsolidated real estate venture Income (Loss)	(9,586)	(269)	(195)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	0
3151 Market Street Venture
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	76.00%
Investments in equity securities	$ 168,925	90,645
Company's unconsolidated real estate venture Income (Loss)	(105)	(72)	(8)
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 0	$ 0
One Uptown - Office
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	62.00%	57.00%
Investments in equity securities	$ 60,677	$ 47,036
Company's unconsolidated real estate venture Income (Loss)	(201)	0	$ 0
Unconsolidated Real Estate Venture Debt at 100%, gross	$ 69,047	$ 51,701