Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Net loss	$ (70)	$ (329)	$ (195)	$ (338)
Cash flow hedging activities:
Gain (loss) on cash flow hedges before reclassification adjustment for cash flow hedges realized in net loss	38	(44)	42	(34)
Reclassification adjustment for (gain) loss on cash flow hedges realized in net loss	10	(4)	19	(14)
Foreign currency translation loss	(5)	(4)	(7)	(1)
Income tax benefit	2	2	3	4
Other comprehensive income (loss)	45	(50)	57	(45)
Comprehensive loss	(25)	(379)	(138)	(383)
Comprehensive (income) attributable to the noncontrolling interest	0	0	0	0
Comprehensive loss attributable to Calpine	$ (25)	$ (379)	$ (138)	$ (383)

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