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Joint Venture, Funding From Debt

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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

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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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Net rentable area for properties owned.

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The number of real estate properties owned as of the balance sheet date.

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The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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The book value of investments in real estate joint ventures including direct and indirect investments.

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INVESTMENT IN UNCONSOLIDATED REAL ESTATE VENTURES - Mid-Atlantic Office JV (Details) $ in Thousands		12 Months Ended
	Dec. 21, 2020 USD ($) ft² property	Dec. 31, 2023 USD ($) property	Dec. 31, 2022 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of real estate properties \| property		72
Investment in real estate ventures, at equity		$ 552,494	$ 532,224
Mid-Atlantic Office JV Loan
Schedule of Equity Method Investments [Line Items]
Secured construction loan with total borrowing capacity		18,500
Philadelphia CBD
Schedule of Equity Method Investments [Line Items]
Investment in real estate ventures, at equity		$ 450,136	$ 387,301
Mid-Atlantic Office JV
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	40.00%	40.00%
Ownership percentage of total common equity	20.00%
Joint venture, funding from debt	$ 147,400
Proceeds from issuance of secured debt	$ 120,800
Mid-Atlantic Office JV \| Mid-Atlantic Office JV Loan \| Maximum
Schedule of Equity Method Investments [Line Items]
Debt instrument, interest rate, stated percentage		5.70%
Mid-Atlantic Office JV \| Mid-Atlantic Office JV Loan \| LIBOR
Schedule of Equity Method Investments [Line Items]
Basis spread on interest rate (as percent)		3.15%
Mid-Atlantic Office JV \| Preferred Equity Securities
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	25.00%
Investment in real estate ventures, at equity	$ 20,000
Mid-Atlantic Office JV \| Common Equity Securities
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	15.00%
Office Properties \| Mid-Atlantic Office JV
Schedule of Equity Method Investments [Line Items]
Number of real estate properties \| property	12
Rentable area (in square feet) \| ft²	1,128,645
Aggregate sales price	$ 192,900
Office Properties \| Mid-Atlantic Office JV \| Philadelphia CBD
Schedule of Equity Method Investments [Line Items]
Number of real estate properties \| property	9
Office Properties \| Mid-Atlantic Office JV \| Metropolitan D C
Schedule of Equity Method Investments [Line Items]
Number of real estate properties \| property	3