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

Quarterly report [Sections 13 or 15(d)]

Debt, Net - Narrative (Details)

Debt, Net - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
Debt, Net - Narrative (Details) - USD ($) $ in Thousands	Mar. 16, 2026	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Debt
Repayments of debt				$ 400,000	$ 0
Interest costs capitalized		$ 2,200	$ 1,300	$ 5,700	$ 3,300
2.25%, $400,000 aggregate principal \| Unsecured Senior Notes
Debt
Repayments of debt	$ 400,000
Interest rate	2.25%	2.25%		2.25%

- 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.

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+ Details