XML 33 R76.htm IDEA: XBRL DOCUMENT v2.4.1.9
Retirement Benefits - Additional information (Detail) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Person
Dec. 31, 2013
Person
Dec. 31, 2012
Person
Compensation and Retirement Disclosure [Abstract]      
Matched employee contribution 100.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent    
Employee contribution on gross wages 7.00%us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent   6.00%us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Number of employee participating in plan 625cpr_DefinedContributionPlanNumberOfEmployeesParticipating 585cpr_DefinedContributionPlanNumberOfEmployeesParticipating 661cpr_DefinedContributionPlanNumberOfEmployeesParticipating
Contribution expense $ 3,592us-gaap_DefinedContributionPlanCostRecognized $ 3,621us-gaap_DefinedContributionPlanCostRecognized $ 2,809us-gaap_DefinedContributionPlanCostRecognized