Derivative Instruments (Details 4) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Loss) Recognized in OCI (Effective Portion)	$ 0	[1]	$ 13	[1]
Gain (Loss) Reclassified from AOCI into Income (EffectivePortion)	(13)	[1],[2]	(9)	[1],[2]
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Loss) Recognized in OCI (Effective Portion)	0	[3]	13	[3]
Gain (Loss) Reclassified from AOCI into Income (EffectivePortion)	$ (13)	[2],[3],[4]	$ (9)	[2],[3]

[1] We recorded an income tax benefit of nil and $1 million for the three months ended March 31, 2014 and 2013, respectively, in AOCI related to our cash flow hedging activities.

[2] Cumulative cash flow hedge losses attributable to Calpine, net of tax, remaining in AOCI were $148 million at each of March 31, 2014 and December 31, 2013. Cumulative cash flow hedge losses attributable to the noncontrolling interest, net of tax, remaining in AOCI were $11 million at each of March 31, 2014 and December 31, 2013.

[3] We did not record any gain (loss) on hedge ineffectiveness related to our interest rate swaps designated as cash flow hedges during the three months ended March 31, 2014 and 2013.

[4] Includes a loss of $5 million that was reclassified from AOCI to interest expense for the three months ended March 31, 2014 where the hedged transactions are no longer expected to occur.