v2.4.0.8

Assets and Liabilities with Recurring Fair Value Measurements Quantitative Info on Level 3 (Details) (USD $) | Sep. 30, 2014 | Dec. 31, 2013
--- | --- | ---
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Derivative, Fair Value, Net | $ 15,000,000 | $ (144,000,000)
Power Contracts [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Derivative, Fair Value, Net | (3,000,000) | 7,000,000
Power Contracts [Member] | Minimum [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair Value Inputs Quantitative Information | 15.35 | 28.92
Power Contracts [Member] | Maximum [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair Value Inputs Quantitative Information | 191.50 | 53.15
Natural Gas [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Derivative, Fair Value, Net | 10,000,000 | 0
Natural Gas [Member] | Minimum [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair Value Inputs Quantitative Information | 1.98 | 0
Natural Gas [Member] | Maximum [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair Value Inputs Quantitative Information | 22.52 | 0
Power Congestion Products [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Derivative, Fair Value, Net | 3,000,000 | 7,000,000
Power Congestion Products [Member] | Minimum [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair Value Inputs Quantitative Information | (19.56) | (8.79)
Power Congestion Products [Member] | Maximum [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair Value Inputs Quantitative Information | $ 35.30 | $ 11.53

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