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Number of parcels of land.

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REAL ESTATE INVESTMENTS - Textual (Details) $ in Thousands	Apr. 14, 2022 USD ($)	Mar. 31, 2022 USD ($) ft² a parcel	Dec. 31, 2021 USD ($)	Dec. 01, 2021 USD ($) ft² property apartment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investment in real estate ventures		$ 434,555	$ 411,110
Rentable area (in square feet) \| ft²		13,678,136
Principal balance outstanding		$ 1,984,610
Assets held for sale, net		25,205	$ 562
Held-for-sale \| Other - Land
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale, net		$ 25,200
Held-for-sale \| Other - Land \| Metropolitan Washington, D.C. Segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of parcels of land \| parcel		1
Area of land (in acres) \| a		0.8
Held-for-sale \| Other - Land \| Metropolitan Washington, D.C. Segment \| Subsequent Event
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of land	$ 29,700
One Uptown Venture
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investment in real estate ventures				$ 328,400
Number of apartment residence \| apartment				341
Joint venture, funding committed by other party				$ 57,500
Construction loan, percentage of total cost				65.00%
One Uptown Venture \| Construction Loans
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Principal balance outstanding				$ 213,400
One Uptown Venture \| Preferred Stock
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity method investment, ownership percentage				50.00%
One Uptown Venture \| Common Stock
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity method investment, ownership percentage				50.00%
One Uptown Venture \| Class A Workspace
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rentable area (in square feet) \| ft²				348,000
One Uptown Venture \| Street Level Retail
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rentable area (in square feet) \| ft²				15,000
Canyon Partners Real Estate \| One Uptown Venture
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of joint ventures \| property				2