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

Quarterly report [Sections 13 or 15(d)]

Debt, Net - Fair Value of Debt (Details)

Debt, Net - Fair Value of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Carrying Amount
Carrying amount and estimated fair value of debt
Long-term debt	$ 2,579,733	$ 2,767,834
Carrying Amount \| Unsecured Senior Notes
Carrying amount and estimated fair value of debt
Long-term debt	2,125,760	2,521,673
Carrying Amount \| Other fixed-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	0	36,125
Carrying Amount \| Variable-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	453,973	210,036
Estimated Fair Value
Carrying amount and estimated fair value of debt
Long-term debt	2,437,135	2,685,486
Estimated Fair Value \| Unsecured Senior Notes
Carrying amount and estimated fair value of debt
Long-term debt	1,982,991	2,438,332
Estimated Fair Value \| Other fixed-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	0	35,649
Estimated Fair Value \| Variable-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	$ 454,144	$ 211,505

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-10

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-12

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
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-Section 50
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
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-Name Accounting Standards Codification
-Section 50
-Paragraph 11
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
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-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

+ Details