v2.4.1.9
Derivative Instruments (Details 4) (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]    
Interest expense $ 154us-gaap_InterestExpense $ 166us-gaap_InterestExpense
Interest Rate Swap [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Gains (Loss) Recognized in OCI (Effective Portion) (6)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember		 [1],[2] 0us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember		 [1],[2]
Interest expense 1us-gaap_InterestExpense
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember		 1us-gaap_InterestExpense
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
Reclassification out of Accumulated Other Comprehensive Income [Member] | Interest Rate Swap [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Interest expense $ (12)us-gaap_InterestExpense
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember		 [1],[2],[3],[4] $ (13)us-gaap_InterestExpense
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis
= us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember		 [1],[2],[3],[4]
[1] We did not record any gain (loss) on hedge ineffectiveness related to our interest rate swaps designated as cash flow hedges during the three months ended March 31, 2015 and 2014.
[2] We recorded an income tax expense of nil for each of the three months ended March 31, 2015 and 2014, respectively, in AOCI related to our cash flow hedging activities.
[3] Includes a loss of nil and $5 million for the three months ended March 31, 2015 and 2014, respectively, that was reclassified from AOCI to interest expense, where the hedged transactions are no longer expected to occur.
[4] Cumulative cash flow hedge losses attributable to Calpine, net of tax, remaining in AOCI were $154 million and $149 million at March 31, 2015 and December 31, 2014, respectively. Cumulative cash flow hedge losses attributable to the noncontrolling interest, net of tax, remaining in AOCI were $13 million and $12 million at March 31, 2015 and December 31, 2014, respectively.