v3.2.0.727

Acquisition (Details) $ in Millions	Jul. 20, 2015 USD ($) MWh	Jun. 30, 2015 MW	Dec. 31, 2014 USD ($) MW
Business Acquisition [Line Items]
Power generation capacity		10,266	10,365
Fore River Energy Center [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net | $			$ 530
Power generation capacity			809
Subsequent Event [Member]
Business Acquisition [Line Items]
Electricity Sales Volume | MWh	22,000,000
Subsequent Event [Member] | Champion Energy Holding, 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

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Electricity Sales Volume

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 805



-SubTopic 10



-Section 55



-Paragraph 37



-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464



Reference 2: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 805



-SubTopic 20



-Section 50



-Paragraph 1



-Subparagraph (c)



-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

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