XML 57 R40.htm IDEA: XBRL DOCUMENT
v3.4.0.3

Fair Value Measurements (Details 3) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2016 | Mar. 31, 2015
Assets and liabilities measured at fair value on a non-recurring basis |  |
Impairment losses | $ 2,446 | $ 0
Fair value measurement on a recurring basis |  |
Assets and liabilities measured at fair value on a non-recurring basis |  |
Assets | 5,671 |
Assets Held For Sale | Fair value measurement on a nonrecurring basis |  |
Assets and liabilities measured at fair value on a non-recurring basis |  |
Assets | 14,886 |
Assets Held For Sale | Fair value measurement on a nonrecurring basis | Significant Unobservable Inputs (Level 3) |  |
Assets and liabilities measured at fair value on a non-recurring basis |  |
Assets | 14,886 |
Colorado Springs | Real Estate Investment Properties, Net | Fair value measurement on a nonrecurring basis |  |
Assets and liabilities measured at fair value on a non-recurring basis |  |
Impairment losses | 1,600 |
White Marsh, Maryland | Real Estate Investment Properties, Net | Fair value measurement on a nonrecurring basis |  |
Assets and liabilities measured at fair value on a non-recurring basis |  |
Impairment losses | $ 847 |

X
- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2420-110228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
Name: | us-gaap_AssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_AssetsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ofc_AssetsbyTypeAxis=us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentGeographicRegionAxis=ofc_ColoradoSpringsColoradoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ofc_AssetsbyTypeAxis=ofc_RealEstateInvestmentPropertiesNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | invest_InvestmentGeographicRegionAxis=ofc_WhiteMarshMarylandMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |