XML 36 R57.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Organization (Details) | 12 Months Ended
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Dec. 31, 2014 acre sqft
Operating office properties |
Investments in real estate |
Number of real estate properties | 173 us-gaap_NumberOfRealEstateProperties / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingOfficePropertiesMember
Square footage of real estate properties (in square feet) | 16,800,000 us-gaap_AreaOfRealEstateProperty / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingOfficePropertiesMember
Office properties under, or contractually committed for, construction or approved for redevelopment |
Investments in real estate |
Number of real estate properties | 13 us-gaap_NumberOfRealEstateProperties / ofc_RealEstatePropertiesStatusAxis = ofc_OfficePropertiesUnderConstructionRedevelopmentOrContractuallyCommittedForConstructionMember
Square footage of real estate properties (in square feet) | 1,600,000 us-gaap_AreaOfRealEstateProperty / ofc_RealEstatePropertiesStatusAxis = ofc_OfficePropertiesUnderConstructionRedevelopmentOrContractuallyCommittedForConstructionMember
Land Controlled for Future Development [Member] |
Investments in real estate |
Area of land we control (in acres) | 1,464 ofc_AcresOfRealEstateProperty / ofc_RealEstatePropertiesStatusAxis = ofc_LandControlledforFutureDevelopmentMember
Developable square footage of real estate properties (in square feet) | 18,300,000 ofc_DevelopableSquareFeet / ofc_RealEstatePropertiesStatusAxis = ofc_LandControlledforFutureDevelopmentMember
Partially operational, wholesale data center |
Investments in real estate |
The expected stabilization critical load after completion of development (in megawatts) | 19.25 ofc_ExpectedStabilizationCriticalLoad / ofc_RealEstatePropertiesStatusAxis = ofc_PartiallyOperationalWholesaleDataCenterMember
Debt in Default of Payment Terms |
Investments in real estate |
Number of real estate properties | 2 us-gaap_NumberOfRealEstateProperties / us-gaap_DebtInstrumentAxis = ofc_DebtinDefaultofPaymentTermsMember

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 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: | num:areaItemType
Balance Type: | na
Period Type: | instant

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 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

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
- Details
Name: | ofc_RealEstatePropertiesStatusAxis=ofc_LandControlledforFutureDevelopmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ofc_RealEstatePropertiesStatusAxis=ofc_OfficePropertiesUnderConstructionRedevelopmentOrContractuallyCommittedForConstructionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ofc_RealEstatePropertiesStatusAxis=ofc_OperatingOfficePropertiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ofc_RealEstatePropertiesStatusAxis=ofc_PartiallyOperationalWholesaleDataCenterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=ofc_DebtinDefaultofPaymentTermsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |