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

Organization (Details)

v3.25.4

Organization (Details) - 12 months ended Dec. 31, 2025 ft² in Thousands	property	ft²	a	shares
Preferred Units
Investments in real estate
Limited partners' capital account, units outstanding (in shares) \| shares				0
COPT Defense Properties, L.P. \| Common Units \| COPT Defense Properties
Investments in real estate
Percentage ownership in operating partnership	97.50%
Unconsolidated Real Estate Joint Ventures
Investments in real estate
Number of real estate properties	24
Operating Properties, Net \| Defense/IT Portfolio
Investments in real estate
Number of real estate properties	201
Area of real estate property (in sqft or acres) \| ft²		23,200
Operating Properties, Net \| Defense/IT Portfolio \| Unconsolidated Real Estate Joint Ventures
Investments in real estate
Number of real estate properties	24
Area of real estate property (in sqft or acres) \| ft²		4,300
Operating Properties, Net \| Other \| Greater Washington, DC/Baltimore
Investments in real estate
Number of real estate properties	6
Area of real estate property (in sqft or acres) \| ft²		2,000
Properties Under Development \| Defense/IT Portfolio
Investments in real estate
Number of real estate properties	5
Area of real estate property (in sqft or acres) \| ft²		646
Land controlled for development \| Defense/IT Portfolio
Investments in real estate
Area of real estate property (in sqft or acres)		10,600	1,000
Land controlled for development \| Other \| Greater Washington, DC/Baltimore
Investments in real estate
Area of real estate property (in sqft or acres) \| a			50

- Definition

Area of a real estate property.

+ References

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- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
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- Definition

The number of limited partner units outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-Publisher FASB
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The number of real estate properties owned as of the balance sheet date.

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