v2.4.0.8

Acquisition (Details) (USD $) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2014 MW | 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% |  |
Proceeds from Sale of Productive Assets | $ 1,570,000,000 |  |
Power generation capacity | 9,849 |  | 9,427
Number of 525 MW generation blocks to be acquired in the Guadalupe acquisition | 2 |  |
Guadalupe Energy Center [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 1,050 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net | 625,000,000 |  |
Guadalupe Expansion Capacity [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 400 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net | 15,000,000 |  |
Incremental CCFC Term Loans [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Debt Instrument, Face Amount | 425,000,000 |  |
Oneta Energy Center [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 1,134 |  |
Carville Energy Center [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 501 | [1] |
Decatur Energy Center [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 795 |  |
Hog Bayou Energy Center [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 237 |  |
Santa Rosa Energy Center [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 225 |  |
Columbia Energy Center [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 606 | [1] |
Six Power Plants [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Power generation capacity | 3,498 |  |
Minimum [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property | 725,000,000 |  |
Maximum [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property | $ 775,000,000 |  |
[1] | Indicates combined-cycle cogeneration power plant.

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