COPT Defense Properties Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details
Uncategorized
- Uncategorized Items - ofc-20180930.xml

Commitments and Contingencies - Narrative (Details)

v3.10.0.1

Commitments and Contingencies - Narrative (Details)	May 25, 2017 USD ($)	Sep. 30, 2018 USD ($) Property	Dec. 31, 2017 USD ($)	Aug. 31, 2010 USD ($)
Capital Leases
Capital lease term	99 years
Purchase option	$ 1
Capital lease obligation	$ 16,100,000	$ 660,000	$ 15,853,000
Minimum rental payments due in 2020		$ 660,000
Environmental Indemnity Agreement
Number of properties which were provided environmental indemnifications \| Property		3
Maximum additional costs agreed to be paid by the entity under environmental indemnification agreement		$ 19,000,000
Development and Redevelopment Obligations
Capital Leases
Purchase obligations		163,100,000
Capital Expenditures For Operating Properties
Capital Leases
Purchase obligations		39,700,000
Third Party Construction
Capital Leases
Purchase obligations		3,600,000
Other Obligations
Capital Leases
Purchase obligations		$ 2,100,000
Specialty Tax Guarantee \| Anne Arundel County, Maryland \| Tax Incremental Financing Bond
Loss Contingencies [Line Items]
Loan amount				$ 30,000,000

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

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