v3.3.0.814

Acquisition (Details) $ in Millions | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2015 USD ($) | Dec. 31, 2015 MWh | Oct. 12, 2015 USD ($) MW | Oct. 01, 2015 USD ($) | Dec. 31, 2014 USD ($) MW
Fore River Energy Center [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business combination, recognized identifiable assets acquired and liabilities assumed, net |  |  |  |  | $ 530
Power generation capacity | MW |  |  |  |  | 731
Osprey Energy Center [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Proceeds from Sale of Productive Assets | $ 166 |  |  |  |
Osprey Energy Center Agreement Term | 27 months |  |  |  |
Subsequent event [Member] | Granite Ridge Energy Center [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business combination, recognized identifiable assets acquired and liabilities assumed, net |  |  | $ 500 |  |
Power generation capacity | MW |  |  | 745 |  |
Subsequent event [Member] | Crane Champion Holdco, LLC [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Ownership percentage of acquiree |  |  |  | 75.00% |
Subsequent event [Member] | EDF Trading North America, LLC [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Ownership percentage of acquiree |  |  |  | 25.00% |
Subsequent event [Member] | Champion Energy Marketing, LLC [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business combination, recognized identifiable assets acquired and liabilities assumed, net |  |  |  | $ 240 |
Electricity sales volume | MWh |  | 22,000,000 |  |  |

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