Real Estate Joint Ventures - Investments in Unconsolidated Real Estate Joint Ventures (Details) $ in Thousands	Mar. 31, 2024 USD ($) property	Dec. 31, 2023 USD ($)
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated real estate joint ventures	$ 40,597	$ 41,052
Other liabilities	$ 16,406	18,996
Unconsolidated Real Estate Joint Ventures
Schedule of Equity Method Investments [Line Items]
Number of Properties \| property	24
Carrying value of Investments	$ 37,615	38,275
Other liabilities	$ 3,000	2,800
Redshift JV LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	3
Carrying value of Investments	$ 21,021	21,053
BREIT COPT DC JV LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	9
Carrying value of Investments	$ 10,321	10,629
Quark JV LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	2
Carrying value of Investments	$ 6,722	6,727
B RE COPT DC JV III LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	2
Carrying value of Investments	$ 2,533	2,643
B RE COPT DC JV II LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	8
Carrying value of Investments	$ (2,982)	(2,777)
Difference between the joint venture's cost basis and the entity's share of underlying equity in the net assets	$ 6,800	$ 6,800

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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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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Amount of investment in equity method investee and investment in and advance to affiliate.

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

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Amount of liabilities classified as other.

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