v3.4.0.3

Acquisition (Details) $ in Millions	Apr. 01, 2016 MW	Feb. 05, 2016 USD ($) MW	Oct. 01, 2015 USD ($)
Granite Ridge Energy Center [Member]
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, net | $		$ 500
Power generation capacity		745
Summer Peaking Capacity		695
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
South Point Energy Center [Member]
Business Acquisition [Line Items]
Summer Peaking Capacity	504

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Ownership Percentage of Acquiree

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Power generation capacity

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Summer Peaking Capacity

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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=73531372&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=73530397&loc=d3e4845-128472

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