Fair Value Accounting, Derivatives (Details) (Cleco Power [Member], Forward Starting Interest Rate Swap [Member], USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
Nov. 14, 2011	Dec. 31, 2012	Dec. 31, 2011
Cleco Power [Member] \| Forward Starting Interest Rate Swap [Member]
Interest rate cash flow hedge [Abstract]
Amount of original notional amount issuance delayed	$ 50.0
Rate basis	spot 30-year all-in swap
Fixed interest rate (in hundredths)	3.05%
Notional amount	50.0
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion		1.2
Derivative Instruments, Loss Recognized in Other Comprehensive Income (Loss), Effective Portion			3.3
Derivative Assets		2.6	3.3
Cash flow hedge ineffectiveness deferred as a regulatory asset		$ 0.5

Cash Flow Hedge Ineffectiveness Deferred as Regulatory Asset

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- Definition

Notional Amount of Derivatives, Delayed Issuance

+ References

No definition available.

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- 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

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- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 6

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-Name FASB Staff Position (FSP)

-Number FIN39-1

-Paragraph 10A, 10B

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-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 4, 17

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

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-Paragraph 5

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph b

-Clause 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

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-Paragraph 10A

-Subparagraph (d)

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-Name Accounting Standards Codification

-Topic 815

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-Section 50

-Paragraph 4C

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

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- Definition

The effective portion of losses on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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- Definition

Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

+ References

No definition available.

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