Consolidated Condensed Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (594)	$ (52)
Cash flow hedging activities:
Gain (loss) on cash flow hedges before reclassification adjustment for cash flow hedges realized in net loss	48	(15)
Reclassification adjustment for loss on cash flow hedges realized in net loss	7	11
Foreign currency translation gain (loss)	(6)	2
Income tax expense	(11)	0
Other comprehensive income (loss)	38	(2)
Comprehensive loss	(556)	(54)
Comprehensive (income) attributable to the noncontrolling interest	(6)	(4)
Comprehensive loss attributable to Calpine	$ (562)	$ (58)