Fair Value Measurements--Counterparty Credit Risk (Details) (Concentration of Counterparty Credit Risk)	Mar. 31, 2014 financial_institutions
Concentration of Counterparty Credit Risk
Concentration Risk [Line Items]
Derivative contracts, number of counterparties	12
Derivative contracts, number of counterparties subject to offset under credit facility	11

Derivative contracts, number of counterparties subject to rights of offset under credit facility

No definition available.

Name:	cpr_DerivativeContractsNumberOfCounterpartiesSubjectToOffsetUnderCreditFacility
Namespace Prefix:	cpr_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant