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

Properties, Net - Narrative (Details)

v3.26.3

Properties, Net - Narrative (Details) $ in Thousands		3 Months Ended		9 Months Ended
Properties, Net - Narrative (Details) $ in Thousands	Apr. 23, 2026 USD ($) a property	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)
Real Estate [Line Items]
Sale of non-operating properties, consideration		$ 28,300		$ 28,300
Gain on sales of non-operating properties		$ 7,673	$ 3,018	$ 14,697	$ 3,318
15020 and 15030 Conference Center Drive
Real Estate [Line Items]
Number of leased operating properties subject to ground lease acquired \| property	2
Land Acquisition
Real Estate [Line Items]
Area of real estate property (in acres) \| a	17
Purchase price	$ 43,000

- Definition

Asset Acquisition, Consideration Transferred, Excluding Transaction Costs

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Number of Leased Operating Properties Subject to Ground Lease Acquired

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- Definition

Area of a real estate property.

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-SubTopic 10
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- Definition

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

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-SubTopic 10
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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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