COPT Defense Properties Annual report [Section 13 and 15(d), not S-K Item 405]

Debt, Net - Fair Value of Debt (Details)

Debt, Net - Fair Value of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Carrying Amount
Carrying amount and estimated fair value of debt
Long-term debt	$ 2,767,834	$ 2,391,755
Carrying Amount \| Unsecured Senior Notes
Carrying amount and estimated fair value of debt
Long-term debt	2,521,673	2,122,270
Carrying Amount \| Other fixed-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	36,125	37,381
Carrying Amount \| Variable-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	210,036	232,104
Estimated Fair Value
Carrying amount and estimated fair value of debt
Long-term debt	2,685,486	2,215,514
Estimated Fair Value \| Unsecured Senior Notes
Carrying amount and estimated fair value of debt
Long-term debt	2,438,332	1,946,905
Estimated Fair Value \| Other fixed-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	35,649	35,841
Estimated Fair Value \| Variable-rate debt
Carrying amount and estimated fair value of debt
Long-term debt	$ 211,505	$ 232,768

- 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

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+ Details