v3.6.0.2

Quarterly Consolidated Financial Data (unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended												12 Months Ended
	Dec. 31, 2016		Sep. 30, 2016		Jun. 30, 2016		Mar. 31, 2016		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Operating revenues	$ 1,582		$ 2,355		$ 1,164		$ 1,615		$ 1,436	$ 1,948	$ 1,442	$ 1,646	$ 6,716	$ 6,472	$ 8,030
Income (loss) from operations	234	[1]	462	[1]	140	[1]	3	[1]	22	466	201	166	839	855	1,989
Net income (loss) attributable to Calpine	$ 24		$ 295		$ (29)		$ (198)		$ (47)	$ 273	$ 19	$ (10)	$ 92	$ 235	$ 946
Net income (loss) per common share attributable to Calpine — basic (in dollars per share)	$ 0.07		$ 0.83		$ (0.08)		$ (0.56)		$ (0.13)	$ 0.77	$ 0.05	$ (0.03)	$ 0.26	$ 0.65	$ 2.34
Net income (loss) per common share attributable to Calpine — diluted (in dollars per share)	$ 0.07		$ 0.83		$ (0.08)		$ (0.56)		$ (0.13)	$ 0.76	$ 0.05	$ (0.03)	$ 0.26	$ 0.64	$ 2.31
Gain (Loss) on Disposition of Assets													$ 157	$ 0	$ 753
[1] We recorded a gain on sale of assets, net of $(157) million in connection with the sale of the Mankato Power Plant which is included in income from operations on our Consolidated Statement of Operations for the year ended December 31, 2016.

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