COPT Defense Properties Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

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

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

v3.26.3

Real Estate Joint Ventures - Investments in Unconsolidated Real Estate Joint Ventures (Details) $ in Thousands	Sep. 30, 2026 USD ($) property	Dec. 31, 2025 USD ($)
Unconsolidated Real Estate Joint Ventures
Schedule of Equity Method Investments [Line Items]
Number of Properties \| property	24
Carrying Value of Investment	$ 11,168	$ 13,525
Unconsolidated Real Estate Joint Ventures \| Balance Sheet Location [Axis]: us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
Schedule of Equity Method Investments [Line Items]
Carrying Value of Investment	35,800	36,400
Unconsolidated Real Estate Joint Ventures \| Balance Sheet Location [Axis]: us-gaap:OtherLiabilities
Schedule of Equity Method Investments [Line Items]
Carrying Value of Investment	$ (24,600)	(22,800)
Redshift JV LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	3
Carrying Value of Investment	$ 20,090	20,767
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	$ 9,077	8,941
Quark JV LLC
Schedule of Equity Method Investments [Line Items]
Nominal Ownership %	10.00%
Number of Properties \| property	2
Carrying Value of Investment	$ 6,604	6,660
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	$ (917)	(600)
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	$ (23,686)	(22,243)
Difference between the joint venture's lower cost basis and the entity's share of underlying equity in the net assets	$ 6,300	$ 6,500

- Definition

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

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