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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Net rentable area for properties owned.

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INVESTMENT IN UNCONSOLIDATED REAL ESTATE VENTURES - Brandywine - AI Venture (Details) $ in Thousands		12 Months Ended
	Nov. 09, 2021 USD ($) ft²	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Schedule of Equity Method Investments [Line Items]
Net gain on real estate venture transactions		$ 181	$ 26,718	$ 2,973
Fairview Properties \| Brandywine - AI Venture LLC
Schedule of Equity Method Investments [Line Items]
Provision for impairment on assets held for sale				1,400
Fairview Properties \| Brandywine - AI Venture LLC \| Brandywine Realty Trust
Schedule of Equity Method Investments [Line Items]
Provision for impairment on assets held for sale				$ 700
Falls Church, Virginia \| Brandywine - AI Venture LLC
Schedule of Equity Method Investments [Line Items]
Rentable area (in square feet) \| ft²	183,618
Aggregate sales price	$ 27,600
Gross proceeds from sale	12,600
Net gain on real estate venture transactions	$ 3,000