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

Properties, Net (Details 4)

v3.7.0.1

Properties, Net (Details 4) ft² in Thousands, $ in Millions		3 Months Ended
Properties, Net (Details 4) ft² in Thousands, $ in Millions	Feb. 15, 2017 USD ($) ft²	Mar. 31, 2017 USD ($) ft² Property
Construction and Redevelopment Activities
Sale price of land \| $		$ 14.3
Gain on sale of land \| $		$ 4.2
Office properties under, or contractually committed for, construction or approved for redevelopment
Construction and Redevelopment Activities
Square footage of real estate properties (in square feet) \| ft²		1,300
Number of real estate properties \| Property		9
Newly redeveloped properties placed in service
Construction and Redevelopment Activities
Square feet of properties placed in service \| ft²		86
Number of real estate properties \| Property		3
Properties under construction or contractually committed for construction
Construction and Redevelopment Activities
Square footage of real estate properties (in square feet) \| ft²		1,300
Number of real estate properties \| Property		8
Properties completed Held-for-future lease \| Office properties under, or contractually committed for, construction or approved for redevelopment
Construction and Redevelopment Activities
Number of real estate properties \| Property		2
Properties under or approved for redevelopment
Construction and Redevelopment Activities
Square footage of real estate properties (in square feet) \| ft²		14
Number of real estate properties \| Property		1
Operating Properties \| Northern Virginia Defense/IT \| Defense/Information Technology Locations \| 3120 Fairview Park Drive
Construction and Redevelopment Activities
Square footage of real estate properties (in square feet) \| ft²	190
Transaction value \| $	$ 39.0

- Definition

The amount of square footage placed into service during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	ofc_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the total transaction value of operating property dispositions during the period.

+ References

No definition available.

+ Details

Name:	ofc_TransactionValueofOperatingPropertyDispositions
Namespace Prefix:	ofc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from the sale of land held for investment; excludes sales of land held as inventory or productive use.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

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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

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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