XML 64 R47.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Properties, Net (Details 4) ft² in Thousands, $ in Thousands |  |  |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | --- | --- | ---
Aug. 07, 2015 USD ($) ft² | Apr. 15, 2015 USD ($) ft² | Mar. 19, 2015 USD ($) ft² | Jun. 30, 2016 USD ($) | Jun. 30, 2015 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2015 USD ($)
2015 Acquisitions |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Contributed revenues |  |  |  | $ 9,200 | $ 4,000 | $ 18,400 | $ 4,300
Contributed net income from continuing operations |  |  |  | $ 1,100 | $ 40 | $ 2,000 | $ 210
250 W Pratt St | Baltimore, Maryland |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Square footage of real estate properties (in square feet) | ft² |  |  | 367 |  |  |  |
Acquired property percentage leased |  |  | 96.20% |  |  |  |
Total acquisition cost |  |  | $ 61,800 |  |  |  |
2600 Park Tower Drive | Northern Virginia |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Square footage of real estate properties (in square feet) | ft² |  | 237 |  |  |  |  |
Acquired property percentage leased |  | 100.00% |  |  |  |  |
Total acquisition cost |  | $ 80,500 |  |  |  |  |
100 and 30 Light Street | Baltimore, Maryland |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Square footage of real estate properties (in square feet) | ft² | 558 |  |  |  |  |  |
Acquired property percentage leased | 93.50% |  |  |  |  |  |
Total acquisition cost | $ 121,200 |  |  |  |  |  |
Business combination, liabilities assumed | 55,000 |  |  |  |  |  |
Fair value assumption of debt | $ 55,500 |  |  |  |  |  |

X
- Definition The percentage of acquired property that is leased at the time of acquisition, expressed as a percent. + References No definition available. + Details
Name: | ofc_AcquiredPropertyPercentageLeased
Namespace Prefix: | ofc_
Data Type: | num:percentItemType
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 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_BusinessAcquisitionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13476-108611 + Details
Name: | us-gaap_DebtInstrumentFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=ofc_TwoThousandFifteenPropertyAcquisitionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=ofc_A250WPrattStMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=ofc_BaltimoreMarylandMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=ofc_A2600ParkTowerDriveMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=ofc_ViennaVirginiaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=ofc_Number100and30LightStreetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |