v2.4.1.9
Commitments and Contingencies (Schedule of Guarantor Obligations) (Details) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2014
Loans Payable [Member]  
Guarantor Obligations [Line Items]  
Guarantee Obligations Balance On First Anniversary $ 37cpn_GuaranteeObligationsBalanceOnFirstAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_LoansPayableMember		 [1]
Guarantee Obligations Balance On Second Anniversary 36cpn_GuaranteeObligationsBalanceOnSecondAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_LoansPayableMember		 [1]
Guarantee Obligations Balance On Third Anniversary 26cpn_GuaranteeObligationsBalanceOnThirdAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_LoansPayableMember		 [1]
Guarantee Obligations Balance On Fourth Anniversary 31cpn_GuaranteeObligationsBalanceOnFourthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_LoansPayableMember		 [1]
Guarantee Obligations Balance On Fifth Anniversary 30cpn_GuaranteeObligationsBalanceOnFifthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_LoansPayableMember		 [1]
Guarantee Obligations Due After Five Years 148cpn_GuaranteeObligationsDueAfterFiveYears
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_LoansPayableMember		 [1]
Guarantor Obligations, Maximum Exposure, Undiscounted 308us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_LoansPayableMember		 [1]
Financial Standby Letter of Credit [Member]  
Guarantor Obligations [Line Items]  
Guarantee Obligations Balance On First Anniversary 572cpn_GuaranteeObligationsBalanceOnFirstAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_FinancialStandbyLetterOfCreditMember		 [2],[3],[4]
Guarantee Obligations Balance On Second Anniversary 14cpn_GuaranteeObligationsBalanceOnSecondAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_FinancialStandbyLetterOfCreditMember		 [2],[3],[4]
Guarantee Obligations Balance On Third Anniversary 20cpn_GuaranteeObligationsBalanceOnThirdAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_FinancialStandbyLetterOfCreditMember		 [2],[3],[4]
Guarantee Obligations Balance On Fourth Anniversary 0cpn_GuaranteeObligationsBalanceOnFourthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_FinancialStandbyLetterOfCreditMember		 [2],[3],[4]
Guarantee Obligations Balance On Fifth Anniversary 0cpn_GuaranteeObligationsBalanceOnFifthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_FinancialStandbyLetterOfCreditMember		 [2],[3],[4]
Guarantee Obligations Due After Five Years 38cpn_GuaranteeObligationsDueAfterFiveYears
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_FinancialStandbyLetterOfCreditMember		 [2],[3],[4]
Guarantor Obligations, Maximum Exposure, Undiscounted 644us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_FinancialStandbyLetterOfCreditMember		 [2],[3],[4]
Surety Bonds [Member]  
Guarantor Obligations [Line Items]  
Guarantee Obligations Balance On First Anniversary 0cpn_GuaranteeObligationsBalanceOnFirstAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_SuretyBondsMember		 [2],[5],[6]
Guarantee Obligations Balance On Second Anniversary 0cpn_GuaranteeObligationsBalanceOnSecondAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_SuretyBondsMember		 [2],[5],[6]
Guarantee Obligations Balance On Third Anniversary 0cpn_GuaranteeObligationsBalanceOnThirdAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_SuretyBondsMember		 [2],[5],[6]
Guarantee Obligations Balance On Fourth Anniversary 0cpn_GuaranteeObligationsBalanceOnFourthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_SuretyBondsMember		 [2],[5],[6]
Guarantee Obligations Balance On Fifth Anniversary 0cpn_GuaranteeObligationsBalanceOnFifthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_SuretyBondsMember		 [2],[5],[6]
Guarantee Obligations Due After Five Years 4cpn_GuaranteeObligationsDueAfterFiveYears
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_SuretyBondsMember		 [2],[5],[6]
Guarantor Obligations, Maximum Exposure, Undiscounted 4us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_SuretyBondsMember		 [2],[5],[6]
Greenleaf [Member]  
Guarantor Obligations [Line Items]  
Guarantee Obligations Balance On First Anniversary 4cpn_GuaranteeObligationsBalanceOnFirstAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GreenleafMember		 [2]
Guarantee Obligations Balance On Second Anniversary 0cpn_GuaranteeObligationsBalanceOnSecondAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GreenleafMember		 [2]
Guarantee Obligations Balance On Third Anniversary 0cpn_GuaranteeObligationsBalanceOnThirdAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GreenleafMember		 [2]
Guarantee Obligations Balance On Fourth Anniversary 0cpn_GuaranteeObligationsBalanceOnFourthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GreenleafMember		 [2]
Guarantee Obligations Balance On Fifth Anniversary 0cpn_GuaranteeObligationsBalanceOnFifthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GreenleafMember		 [2]
Guarantee Obligations Due After Five Years 0cpn_GuaranteeObligationsDueAfterFiveYears
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GreenleafMember		 [2]
Guarantor Obligations, Maximum Exposure, Undiscounted 4us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GreenleafMember		 [2]
Gurantee Obligations Total [Member]  
Guarantor Obligations [Line Items]  
Guarantee Obligations Balance On First Anniversary 613cpn_GuaranteeObligationsBalanceOnFirstAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GuranteeObligationsTotalMember
Guarantee Obligations Balance On Second Anniversary 50cpn_GuaranteeObligationsBalanceOnSecondAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GuranteeObligationsTotalMember
Guarantee Obligations Balance On Third Anniversary 46cpn_GuaranteeObligationsBalanceOnThirdAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GuranteeObligationsTotalMember
Guarantee Obligations Balance On Fourth Anniversary 31cpn_GuaranteeObligationsBalanceOnFourthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GuranteeObligationsTotalMember
Guarantee Obligations Balance On Fifth Anniversary 30cpn_GuaranteeObligationsBalanceOnFifthAnniversary
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GuranteeObligationsTotalMember
Guarantee Obligations Due After Five Years 190cpn_GuaranteeObligationsDueAfterFiveYears
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GuranteeObligationsTotalMember
Guarantor Obligations, Maximum Exposure, Undiscounted $ 960us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= cpn_GuranteeObligationsTotalMember
[1] Represents Calpine Corporation guarantees of certain power plant capital leases and related interest. All guaranteed capital leases are recorded on our Consolidated Balance Sheets.
[2] These are contingent off balance sheet obligations.
[3] Letters of credit are renewed annually and as such all amounts are reflected in the year of letter of credit expiration. The related commercial obligations extend for multiple years, therefore, renewal of the letter of credit will likely follow the term of the associated commercial obligation.
[4] The standby letters of credit disclosed above represent those disclosed in Note 6.
[5] The majority of surety bonds do not have expiration or cancellation dates.
[6] As of December 31, 2014, $2 million of cash collateral is outstanding related to these bonds.