v2.4.0.8

Derivative Instruments (Details) (USD $) In Millions, unless otherwise specified | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2014 t MWh MMBTU | Dec. 31, 2013 t MWh MMBTU
Derivative Instruments [Abstract] |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | (49) | (29)
Nonmonetary Notional Amount of Price Risk Derivatives Natural Gas | 316 | 448
Derivative, Nonmonetary Notional Amount, Mass | 2 | 0
Price Risk Derivatives [Abstract] |  |
Derivative, Notional Amount | $ 1,510 | $ 1,527

X
- Details
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- Definition Nonmonetary Notional Amount of Price Risk Derivatives Natural Gas + References No definition available. + Details
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X
- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Nominal energy measure used to calculate payments on a derivative instrument. + References No definition available. + Details
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- Definition Nominal mass used to calculate payments on a derivative instrument. + References No definition available. + Details
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