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

Interest Rate Derivatives - Schedule of Key Terms and Fair Values of Interest Rate Swap Derivatives (Details)

v3.26.3

Interest Rate Derivatives - Schedule of Key Terms and Fair Values of Interest Rate Swap Derivatives (Details) - USD ($) $ in Thousands	Aug. 01, 2026	Feb. 02, 2026	Dec. 31, 2025
Fair values of interest rate swap derivatives
Fair value of interest rate swaps			$ 107
Interest rate swap, effective August 1, 2019 \| Designated
Fair values of interest rate swap derivatives
Notional Amount	$ 10,020
Fixed Rate	1.678%
Floating Rate Index (over SOFR)	0.10%
Fair value of interest rate swaps			114
Interest rate swap, effective February 1, 2023 3.742 % \| Designated
Fair values of interest rate swap derivatives
Notional Amount		$ 150,000
Fixed Rate		3.742%
Fair value of interest rate swaps			(5)
Interest rate swap, effective February 1, 2023 3.747% \| Designated
Fair values of interest rate swap derivatives
Notional Amount		$ 50,000
Fixed Rate		3.747%
Fair value of interest rate swaps			$ (2)

- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-5

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-5A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
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-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

+ References

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