v2.4.0.8

Acquisition (Details) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2014 MW		Sep. 30, 2013	Sep. 30, 2014 MW		Sep. 30, 2013	Dec. 31, 2013 MW
Business Acquisition [Line Items]
Number of power plants to be disposed of	6
Ownership percentage before divestiture of business	100.00%			100.00%
Working Capital Adjustment to Sale price	$ 2,000,000
Business Combination, Contingent Consideration, Liability	16,000,000			16,000,000
Gain (Loss) on Disposition of Assets	753,000,000		0	753,000,000		0
Power generation capacity	10,365			10,365			9,427
Fore River Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	809			809
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	530,000,000			530,000,000
Guadalupe Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	1,050			1,050
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	625,000,000			625,000,000
Guadalupe Expansion Capacity [Member]
Business Acquisition [Line Items]
Power generation capacity	400			400
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	15,000,000			15,000,000
Incremental CCFC Term Loans [Member]
Business Acquisition [Line Items]
Debt Instrument, Face Amount	425,000,000			425,000,000
Oneta Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	1,134			1,134
Carville Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	501	[1]		501	[1]
Decatur Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	795			795
Hog Bayou Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	237			237
Santa Rosa Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	225			225
Columbia Energy Center [Member]
Business Acquisition [Line Items]
Power generation capacity	606	[1]		606	[1]
Six Power Plants [Member]
Business Acquisition [Line Items]
Proceeds from Sale of Productive Assets	$ 1,570,000,000
Power generation capacity	3,498			3,498
[1] Indicates combined-cycle cogeneration power plant.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Face (par) amount of debt instrument at time of issuance.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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