Consolidated Statements of Operations - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating revenues:
Commodity revenue		$ 9,865	$ 8,836	$ 6,943
Mark to Market Gain Loss on Derivatives included in Operating Revenues		(373)	(101)	(245)
Other revenue		20	17	18
Operating revenues	[1]	9,512	8,752	6,716
Operating expenses:
Commodity expense		6,914	6,268	4,431
Mark to Market Gain Loss on Derivatives Included in Fuel and Purchased Energy Expense		(165)	70	(244)
Fuel and purchased energy expense		6,749	6,338	4,187
Operating and maintenance expense		1,020	1,080	977
Depreciation and amortization expense		739	724	662
General and other administrative expense		158	155	140
Other operating expenses		98	85	79
Total operating expenses		8,764	8,382	6,045
Impairment losses		10	41	13
(Gain) on sale of assets, net		0	(27)	(157)
(Income) from unconsolidated subsidiaries		(24)	(22)	(24)
Income from operations		762	378	839
Interest expense		617	621	631
(Gain) loss on extinguishment of debt		(28)	38	25
Other (income) expense, net		81	32	24
Income before income taxes		92	(313)	159
Income tax expense		64	8	48
Net income (loss)		28	(321)	111
Net income attributable to the noncontrolling interest		(18)	(18)	(19)
Net income (loss) attributable to Calpine		$ 10	$ (339)	$ 92

[1] Includes intersegment revenues of $488 million, $324 million and $20 million in the West, $573 million, $361 million and $81 million in Texas, $234 million, $237 million and $48 million in the East and $4 million, $4 million, $2 million in Retail for the years ended December 31, 2018, 2017 and 2016, respectively.