Consolidated Condensed Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss	$ (7)us-gaap_ProfitLoss	$ (13)us-gaap_ProfitLoss
Cash flow hedging activities:
Loss on cash flow hedges before reclassification adjustment for cash flow hedges realized in net loss	(18)	(13)
Reclassification adjustment for loss on cash flow hedges realized in net loss	12	13
Foreign currency translation loss	(12)	(6)
Income tax expense	0us-gaap_OtherComprehensiveIncomeLossTax	0us-gaap_OtherComprehensiveIncomeLossTax
Other comprehensive loss	(18)	(6)
Comprehensive loss	(25)	(19)
Comprehensive (income) attributable to the noncontrolling interest	(2)	(4)
Comprehensive loss attributable to Calpine	$ (27)us-gaap_ComprehensiveIncomeNetOfTax	$ (23)us-gaap_ComprehensiveIncomeNetOfTax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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