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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