Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2011	Jun. 30, 2011
Business Acquisition [Line Items]
Ownership interest percentage in facility's common assets		50.00%
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 plant		415
Construction expenditures included in accounts payable		109.5
Additional Renewal Period Of License	20
Impairment of Vermont Yankee		$ 0
Cleco Power [Member]
Business Acquisition [Line Items]
Ownership interest percentage in facility's common assets		50.00%

Additional renewal period of license.

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Generating units.

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- Definition

Net carrying value of plant.

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- Definition

Number of combined cycle gas fired generating units.

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- Definition

Percentage of equity interest purchased.

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- Definition

Property Plant and equipment.

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph c

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Carrying value as of the balance sheet date of obligations incurred and payable for the acquisition of merchandise, materials, supplies and services pertaining to construction projects such as a housing development or factory expansion not classified as trade payables. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19
-Subparagraph a
-Article 5

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 26
-Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 7, 25

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