Consolidated Condensed Statements of Operations (Unaudited) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Consolidated Condensed Statements of Operations
Operating Revenues	$ 1,633	$ 1,430	$ 3,132	$ 2,944
Operating expenses:
Fuel and purchased energy expense	1,000	904	2,069	1,873
Plant operating expense	261	213	499	431
Depreciation and amortization expense	131	135	262	271
Sales, general and other administrative expense	34	50	66	72
Other operating expense	22	26	42	52
Total operating expenses	1,448	1,328	2,938	2,699
(Income) from unconsolidated investments in power plants	2	(6)	(7)	(13)
Income from operations	183	108	201	258
Interest expense	192	224	383	405
(Gain) loss on interest rate derivatives, net	37	(8)	146	3
Interest (income)	(2)	(4)	(5)	(6)
Debt extinguishment costs	5	7	98	7
Other (income) expense, net	3	1	10	6
Loss before income taxes and discontinued operations	(52)	(112)	(431)	(157)
Income tax expense (benefit)	18	6	(65)	17
Loss before discontinued operations	(70)	(118)	(366)	(174)
Discontinued operations, net of tax expense		4		12
Net loss	(70)	(114)	(366)	(162)
Net (income) loss attributable to the noncontrolling interest		(1)	(1)
Net loss attributable to Calpine	$ (70)	$ (115)	$ (367)	$ (162)
Basic and diluted loss per common share attributable to Calpine:
Weighted average shares of common stock outstanding (in thousands)	486,411	486,057	486,334	485,989
Loss before discontinued operations attributable to Calpine	$ (0.14)	$ (0.25)	$ (0.75)	$ (0.35)
Discontinued operations, net of tax expense, attributable to Calpine		$ 0.01		$ 0.02
Net loss per common share attributable to Calpine - basic and diluted	$ (0.14)	$ (0.24)	$ (0.75)	$ (0.33)