v3.3.1.900

Acquisitions, Divestitures and Discontinued Operations (Textuals) (Details) $ in Millions | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2014 USD ($) MW | Dec. 31, 2015 USD ($) MWh | Dec. 31, 2014 USD ($) MW | Dec. 31, 2013 USD ($) | Feb. 05, 2016 USD ($) MW | Oct. 01, 2015 USD ($) | Jul. 03, 2014 | Mar. 31, 2014 USD ($) MW
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Amortization of Intangible Assets |  |  | $ 20 | $ 14 | $ 14 |  |  |  |
(Gain) on sale of power plants, net |  |  | 0 | $ 753 | $ 0 |  |  |  |
Fore River Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  | 731 |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  | $ 530 |  |  |  |  |
Guadalupe Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  |  |  |  | 1,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  |  |  |  | $ 625
Guadalupe Expansion Capacity [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  |  |  |  | 400
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  |  |  |  | $ 15
Crane Champion Holdco, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Ownership Percentage of Acquiree |  |  |  |  |  |  | 75.00% |  |
EDF Trading North America, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Ownership Percentage of Acquiree |  |  |  |  |  |  | 25.00% |  |
Champion Energy Marketing, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  |  | $ 240 |  |
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net |  |  |  |  |  |  | 296 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets |  |  |  |  |  |  | 240 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment |  |  |  |  |  |  | 5 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill | [1] |  |  |  |  |  | 575 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets |  |  |  |  |  |  | 46 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets |  |  |  |  |  |  | 866 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities |  |  |  |  |  |  | 396 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other |  |  |  |  |  |  | 174 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities |  |  |  |  |  |  | $ 570 |  |
Amortization of Intangible Assets |  |  | $ 71 |  |  |  |  |  |
Electricity Sales Volume | MWh |  |  | 22,000,000 |  |  |  |  |  |
Osprey Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Sale of Productive Assets |  |  |  | $ 166 |  |  |  |  |
Osprey Energy Center Agreement Term |  |  |  | 27 months |  |  |  |  |
Incremental CCFC Term Loans [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  | $ 425
Six Power Plants [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Sale of Productive Assets |  | $ 1,570 |  |  |  |  |  |  |
Ownership percentage before divestiture of business |  |  |  |  |  |  |  | 100.00% |
Working Capital Adjustment to Sale price |  | 2 |  |  |  |  |  |  |
(Gain) on sale of power plants, net |  | $ 753 |  |  |  |  |  |  |
Columbia Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW | [2] | 606 |  |  |  |  |  |  |
Santa Rosa Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  | 225 |  |  |  |  |  |  |
Hog Bayou Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  | 237 |  |  |  |  |  |  |
Decatur Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  | 795 |  |  |  |  |  |  |
Carville Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW | [2] | 501 |  |  |  |  |  |  |
Oneta Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  | 1,134 |  |  |  |  |  |  |
Six Power Plants [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  | 3,498 |  |  |  |  |  |  |
Customer Relationships [Member] | Champion Energy Marketing, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 7 years |  |  |  |  |  |
Trade Names [Member] | Champion Energy Marketing, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 15 years |  |  |  |  |  |
Subsequent Event [Member] | Granite Ridge Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  | 745 |  |  |
Summer peaking capacity | MW |  |  |  |  |  | 695 |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  | $ 500 |  |  |
[1] | The intangible assets are recorded in other assets on our Consolidated Balance Sheet and consist primarily of acquired customer contracts, which are being amortized over various contract terms, and customer relationships and trade name which are being amortized over seven and 15 years, respectively. For the year ended December 31, 2015, we recorded amortization expense of $71 million related to these intangible assets.
[2] | Indicates combined-cycle cogeneration power plant

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