Property, Plant, and Equipment (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2011	Sep. 30, 2011 MW GeneratingUnit Year MMBtu
Business Acquisition [Line Items]
Ownership interest percentage in facility's common assets		50.00%
Expenditures in Accounts Payable [Line Items]
Construction expenditures included in accounts payable		$ 122.9
Property Plant and Equipment (Textuals) [Abstract]
Generating units		580
Number of combined cycle gas fired generating units		2
Percentage of equity interest purchased		100.00%
Ownership interest in the facility's common assets		300
Net carrying value of the plant, including nuclear fuel		459
Additional Renewal Period Of License	20 years
Impairment of Vermont Yankee		$ 0
Cleco Power [Member]
Business Acquisition [Line Items]
Ownership interest percentage in facility's common assets		50.00%

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Generating units.

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Net carrying value of plant.

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Number of combined cycle gas fired generating units.

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Property Plant and equipment.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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-Name Statement of Financial Accounting Standard (FAS)

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