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Regulatory Matters and Revenues Subject to Refund (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011
Regulated Operations [Abstract] |
Estimated project cost of the natural gas turbine and associated facilities | $ 85.6

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- Definition Estimated project cost of the natural gas turbine and associated facilities. + References No definition available. + Details
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- Details
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