v3.2.0.727

Assets and Liabilities with Recurring Fair Value Measurements Quantitative Info on Level 3 (Details) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Fair Value, Net	$ 384,000,000	$ 271,000,000
Power Contracts [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Fair Value, Net	237,000,000	74,000,000
Power Contracts [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs Quantitative Information	12.68	14.00
Power Contracts [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs Quantitative Information	121.40	122.79
Natural Gas [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Fair Value, Net		5,000,000
Natural Gas [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs Quantitative Information		1.00
Natural Gas [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs Quantitative Information		10.86
Power Congestion Products [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Fair Value, Net	7,000,000	9,000,000
Power Congestion Products [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs Quantitative Information	(19.56)	(19.56)
Power Congestion Products [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs Quantitative Information	$ 19.56	$ 19.56

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- Definition

Fair Value Inputs Quantitative Information

+ References

No definition available.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 815



-SubTopic 10



-Section 45



-Paragraph 6



-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958



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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 815



-SubTopic 10



-Section 45



-Paragraph 5



-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958



Reference 3: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 825



-SubTopic 10



-Section 50



-Paragraph 10



-Subparagraph (a)



-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611



Reference 4: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 825



-SubTopic 10



-Section 50



-Paragraph 15



-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13495-108611

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