Regulatory Assets and Liabilities, Additional Disclosures (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Regulatory Assets [Line Items]
Decrease in fuel and purchased power costs	$ 10,218,000	$ (148,000)
Cleco Power [Member]
Regulatory Assets [Line Items]
Decrease in fuel and purchased power costs	10,218,000	(148,000)
Fuel and purchased power \| Cleco Power [Member]
Regulatory Assets [Line Items]
Percentage of total fuel cost regulated by LPSC (in hundredths)	74.00%
Decrease in under recovered costs	8,700,000
Decrease in fuel and purchased power costs	9,600,000
Increase due to the settlement of previously open FTR positions and a mark-to-market loss on current open FTR positions	$ 900,000

Percentage of the entity's total fuel cost regulated by LPSC.

No definition available.

Name:	cnl_PercentageOfTotalFuelCostRegulated
Namespace Prefix:	cnl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The increase (decrease) during the reporting period in carrying amount of capitalized fuel costs of a regulated entity that are expected to be recoverable through rate adjustments within one year or the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

Name:	us-gaap_IncreaseDecreaseInDeferredFuelCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The increase (decrease) during the period in the carrying value of derivative instruments reported as assets that are due to be disposed of within one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

Name:	us-gaap_IncreaseDecreaseInDerivativeAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The change during the reporting period in the value of the liability created by an under-recovery. An under-recovery means that the basic energy product price based on the daily product price and exchange rate is more than the basic fuel price used in the calculation of the monthly retail energy product.

+ References

+ Details

Name:	us-gaap_IncreaseDecreaseInUnderEnergyRecovery
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_RegulatoryAssetLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=us-gaap_SubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RegulatoryAssetAxis=us-gaap_DeferredFuelCostsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: