COPT Defense Properties Annual report [Section 13 and 15(d), not S-K Item 405]

Annual report [Section 13 and 15(d), not S-K Item 405]

Cover
- Cover Page
- Audit Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Real Estate Joint Ventures - Unconsolidated Real Estate Joint Ventures (Details)

v3.25.4

Real Estate Joint Ventures - Unconsolidated Real Estate Joint Ventures (Details) $ in Thousands	Dec. 31, 2025 USD ($) property	Dec. 31, 2024 USD ($)	Jan. 10, 2023
Unconsolidated Real Estate Joint Ventures
Schedule of Equity Method Investments [Line Items]
Number of Properties \| property	24
Carrying Value of Investment	$ 13,525	$ 35,951
Unconsolidated Real Estate Joint Ventures \| Investment in unconsolidated real estate joint ventures
Schedule of Equity Method Investments [Line Items]
Carrying Value of Investment	36,400	39,400
Unconsolidated Real Estate Joint Ventures \| Other liabilities
Schedule of Equity Method Investments [Line Items]
Carrying Value of Investment	$ (22,800)	(3,400)
Redshift
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%		10.00%
Number of Properties \| property	3
Carrying Value of Investment	$ 20,767	20,921
BREIT COPT DC JV LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	9
Carrying Value of Investment	$ 8,941	9,584
Quark JV LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	2
Carrying Value of Investment	$ 6,660	6,706
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 Investment	$ (600)	2,149
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 Investment	$ (22,243)	(3,409)
Difference between the joint venture's lower cost basis and the entity's share of underlying equity in the net assets	$ 6,500	$ 6,700

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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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