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v2.4.1.9

Income Taxes (Details 2) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Other income tax information |  |  |
Approximate amount by which basis of assets and liabilities for tax reporting purposes is lower than amount reported on consolidated balance sheet | $ 233,000,000 ofc_ApproximateAmountByWhichNetBasisOfAssetsAndLiabilitiesForTaxReportingPurposesIsLowerThanAmountReportedOnConsolidatedBalanceSheet |  |
Deferred income tax (benefit) expense |  |  |
Total income tax expense | 310,000 us-gaap_IncomeTaxExpenseBenefit | 1,978,000 us-gaap_IncomeTaxExpenseBenefit | 381,000 us-gaap_IncomeTaxExpenseBenefit
Deferred Tax Assets, Net [Abstract] |  |  |
Increase in deferred tax asset valuation |  | 1,900,000 us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount |
TRS |  |  |
Other income tax information |  |  |
(Loss) income before income taxes | 822,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 300,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 11,300,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
Deferred income tax (benefit) expense |  |  |
Federal | 258,000 us-gaap_DeferredFederalIncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 1,742,000 us-gaap_DeferredFederalIncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 312,000 us-gaap_DeferredFederalIncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
State | 52,000 us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 236,000 us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 69,000 us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
Total income tax expense | 310,000 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 1,978,000 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 381,000 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
Reconciliation of Federal statutory rate to the effective tax rate |  |  |
Income taxes at U.S. statutory rate (as a percent) | 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
State and local, net of U.S. Federal tax benefit (as a percent) | 4.20%us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 4.50%us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 4.60%us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
Increase in deferred tax asset valuation allowance (as a percent) | 0.00%us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 562.90%us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 0.00%us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
Other (as a percent) | (0.40%)us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | (1.10%)us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 0.00%us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
Effective tax rate (as a percent) | 37.80%us-gaap_EffectiveIncomeTaxRateContinuingOperations / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 600.30%us-gaap_EffectiveIncomeTaxRateContinuingOperations / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 38.60%us-gaap_EffectiveIncomeTaxRateContinuingOperations / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember
Operating Loss Carryforwards | 13,000,000 us-gaap_OperatingLossCarryforwards / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember |  |
Deferred Tax Assets, Net [Abstract] |  |  |
Operating loss forward | 5,012,000 ofc_DeferredTaxAssetsOperatingLosssAndInterestDeductionCarryforwards / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 5,382,000 ofc_DeferredTaxAssetsOperatingLosssAndInterestDeductionCarryforwards / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember |
Share-based compensation | 976,000 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 869,000 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember |
Accrued payroll | 195,000 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | 221,000 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember |
Property | (119,000)us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | (105,000)us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember |
Valuation allowance | (2,062,000)us-gaap_DeferredTaxAssetsValuationAllowance / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | (2,062,000)us-gaap_DeferredTaxAssetsValuationAllowance / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember |
Deferred tax asset, net | $ 4,002,000 us-gaap_DeferredTaxAssetsLiabilitiesNet / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember | $ 4,305,000 us-gaap_DeferredTaxAssetsLiabilitiesNet / dei_LegalEntityAxis = ofc_TaxableReitSubsidiaryMember |
Common Shares |  |  |
Income Tax [Line Items] |  |  |
Ordinary income (as a percent) | 64.50%ofc_DividendsDeclaredOrdinaryIncomePercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember | 71.80%ofc_DividendsDeclaredOrdinaryIncomePercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember | 33.20%ofc_DividendsDeclaredOrdinaryIncomePercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember
Long-term capital gain (as a percent) | 6.50%ofc_DividendsDeclaredLongTermCapitalGainPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember | 22.40%ofc_DividendsDeclaredLongTermCapitalGainPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember | 0.00%ofc_DividendsDeclaredLongTermCapitalGainPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember
Return of capital (as a percent) | 29.00%ofc_DividendsDeclaredReturnOfCapitalPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember | 5.80%ofc_DividendsDeclaredReturnOfCapitalPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember | 66.80%ofc_DividendsDeclaredReturnOfCapitalPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember
Preferred Shares |  |  |
Income Tax [Line Items] |  |  |
Ordinary income (as a percent) | 90.90%ofc_DividendsDeclaredOrdinaryIncomePercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember | 76.20%ofc_DividendsDeclaredOrdinaryIncomePercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember | 100.00%ofc_DividendsDeclaredOrdinaryIncomePercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember
Long-term capital gain (as a percent) | 9.10%ofc_DividendsDeclaredLongTermCapitalGainPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember | 23.80%ofc_DividendsDeclaredLongTermCapitalGainPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember | 0.00%ofc_DividendsDeclaredLongTermCapitalGainPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember
Return of capital (as a percent) | 0.00%ofc_DividendsDeclaredReturnOfCapitalPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember | 0.00%ofc_DividendsDeclaredReturnOfCapitalPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember | 0.00%ofc_DividendsDeclaredReturnOfCapitalPercentage / us-gaap_StatementClassOfStockAxis = us-gaap_PreferredStockMember

X
- Definition Represents the approximate amount by which basis of assets and liabilities for tax reporting purposes are lower than the amount reported on consolidated balance sheet. + References No definition available. + Details
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