v2.3.0.15

Loss Per Share (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Loss Per Share [Abstract]
New shares of reorganized Calpine Corp common stock			485,000,000
Diluted weighted average shares calculation:
Weighted average shares outstanding (basic)	486,420,000	486,088,000	486,363,000	486,023,000
Share-based awards for dilutive adjustment	2,642	1,355		1,176
Weighted average shares outstanding (diluted)	489,062,000	487,443,000	486,363,000	487,199,000
Potentially dilutive securities
Share-based awards	12,696,000	14,625,000	15,202,000	14,193,000

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