Quarterly report pursuant to Section 13 or 15(d)

Organization (Details 2)

v2.4.1.9
Organization (Details 2) (Corporate Office Properties, L.P.)
 3 Months Ended
Mar. 31, 2015
Common Units
  
Forms of ownership in Operating Partnership and ownership percentage by the entity  
Percentage ownership in operating partnership 96.30%us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipInterest
/ dei_LegalEntityAxis
= ofc_CorporateOfficePropertiesLPMember
/ ofc_UnitsByNameAxis
= ofc_CommonUnitsMember
Preferred Units
  
Forms of ownership in Operating Partnership and ownership percentage by the entity  
Percentage ownership in operating partnership 95.50%us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipInterest
/ dei_LegalEntityAxis
= ofc_CorporateOfficePropertiesLPMember
/ ofc_UnitsByNameAxis
= ofc_PreferredUnitsMember