XML 42 R40.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Organization (Details) | 9 Months Ended
--- | ---
Sep. 30, 2012 sqft Property
Operating office properties |
Investments in real estate |
Number of real estate properties | 206
Square footage of real estate properties (in square feet) | 18,600,000
Office properties under construction or redevelopment |
Investments in real estate |
Number of real estate properties | 10
Square footage of real estate properties (in square feet) | 1,200,000
Office properties under construction or redevelopment which are partially operational |
Investments in real estate |
Number of real estate properties | 2
Land held or under pre-construction |
Investments in real estate |
Area of land held or under pre-construction (in acres) | 1,696
Area of land parcels controlled but not owned (in acres) | 572
Developable square footage of real estate properties (in square feet) | 19,800,000
Partially operational, wholesale data center |
Investments in real estate |
The expected stabilization critical load after completion of development (in megawatts) | 18

X
- Definition Represents the area of land parcels in acres. + References No definition available. + Details
Name: | ofc_AcresOfRealEstateProperty
Namespace Prefix: | ofc_
Data Type: | num:areaItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the area of land parcels held or under pre-construction that is controlled but not owned. + References No definition available. + Details
Name: | ofc_AcresOfRealEstatePropertyControlledButNotOwned
Namespace Prefix: | ofc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of square feet into which a land parcel is potentially developable. + References No definition available. + Details
Name: | ofc_DevelopableSquareFeet
Namespace Prefix: | ofc_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the expected stabilization critical load after completion of development of the property. Critical load is the amount of megawatts of power made available for the exclusive use tenants in the property. + References No definition available. + Details
Name: | ofc_ExpectedStabilizationCriticalLoad
Namespace Prefix: | ofc_
Data Type: | num:powerItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of real estate properties owned as of the balance sheet date. + References No definition available. + Details
Name: | us-gaap_NumberOfRealEstateProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_RealEstatePropertiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of square footage related to a real estate property. + References No definition available. + Details
Name: | us-gaap_SquareFootageOfRealEstateProperty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration