Quarterly report pursuant to Section 13 or 15(d)

Borrowings (Senior secured revolving credit facility ) (Details)

v2.4.1.9
Borrowings (Senior secured revolving credit facility ) (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Dec. 31, 2014
Mar. 11, 2014
Line of Credit Facility [Line Items]      
Senior secured revolving credit facility $ 37,000us-gaap_LongTermLineOfCredit $ 35,000us-gaap_LongTermLineOfCredit  
Senior Secured Revolving Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Maximum borrowing capacity     500,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
Current borrowing capacity 250,000us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
   
Senior secured revolving credit facility $ 37,000us-gaap_LongTermLineOfCredit
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
$ 35,000us-gaap_LongTermLineOfCredit
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
 
Interest rate at period end (as a percent) 1.98%us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
   
Unused capacity, commitment fee (as a percent) 0.50%us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
   
Debt Instrument, Maturity Date Mar. 11, 2019    
Senior Secured Revolving Credit Facility [Member] | Minimum [Member]      
Line of Credit Facility [Line Items]      
Basis Spread on LIBOR (as a percent) 1.75%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
   
Senior Secured Revolving Credit Facility [Member] | Maximum [Member]      
Line of Credit Facility [Line Items]      
Basis Spread on LIBOR (as a percent) 2.75%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_DebtInstrumentAxis
= cpe_SeniorSecuredRevolvingCreditFacilityMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember