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v2.4.1.9

Properties, net (Details) (USD $) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2014 | Mar. 31, 2015 | Dec. 31, 2014
Investments in real estate |  |  |
Operating properties, net |  | $ 2,888,534,000 us-gaap_RentalProperties | $ 2,751,488,000 us-gaap_RentalProperties
Greater Philadelphia |  |  |
Investments in real estate |  |  |
Depreciation expense on reclassified assets | 12,900,000 ofc_DepreciationExpenseResultingFromUsefulLifeChange / us-gaap_StatementGeographicalAxis = ofc_GreaterPhiladelphiaMember |  |
Operating properties, net |  |  |
Investments in real estate |  |  |
Less: accumulated depreciation |  | (724,539,000)us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingPropertiesMember | (703,083,000)us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingPropertiesMember
Operating properties, net | Land |  |  |
Investments in real estate |  |  |
Gross |  | 455,639,000 us-gaap_RealEstateGrossAtCarryingValue / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_LandMember / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingPropertiesMember | 439,355,000 us-gaap_RealEstateGrossAtCarryingValue / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_LandMember / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingPropertiesMember
Operating properties, net | Buildings and improvements |  |  |
Investments in real estate |  |  |
Gross |  | $ 3,157,434,000 us-gaap_RealEstateGrossAtCarryingValue / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingAndBuildingImprovementsMember / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingPropertiesMember | $ 3,015,216,000 us-gaap_RealEstateGrossAtCarryingValue / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingAndBuildingImprovementsMember / ofc_RealEstatePropertiesStatusAxis = ofc_OperatingPropertiesMember

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- Definition Additional depreciation expense recognized resulting from a change in the useful life of the disclosed asset. + References No definition available. + Details
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- Definition Amount, before accumulated depreciation, of real estate investments for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule III) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 28 -Article 12 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule III -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28.4) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 + Details
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- Definition The cumulative amount of depreciation for real estate property held for investment purposes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(3)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 7 + Details
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- Details
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- Definition Carrying amount of income producing properties held for rental. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(d)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Details
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