Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation and Other Compensation Matters (Details 5)

v2.4.1.9
Share-Based Compensation and Other Compensation Matters (Details 5) (Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member], Management, USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member] | Management
    
Deferred Compensation Plan    
Maximum percentage of participants' compensation which is deferrable (as a percent) 100.00%ofc_DeferredCompensationArrangementWithIndividualMaximumDeferrablePercentageOfCompensation
/ us-gaap_DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTypeOfDeferredCompensationAxis
= us-gaap_DeferredCompensationExcludingShareBasedPaymentsAndRetirementBenefitsMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_ManagementMember 		 
Balance of the plan which was fully funded $ 5.9us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability
/ us-gaap_DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTypeOfDeferredCompensationAxis
= us-gaap_DeferredCompensationExcludingShareBasedPaymentsAndRetirementBenefitsMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_ManagementMember 		$ 7.5us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability
/ us-gaap_DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTypeOfDeferredCompensationAxis
= us-gaap_DeferredCompensationExcludingShareBasedPaymentsAndRetirementBenefitsMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_ManagementMember