Jointly Owned Generation Units (Details)	Dec. 31, 2016 USD ($) MW	Apr. 13, 2016 USD ($)
Cleco Power [Member]
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 539,014,000
Accumulated depreciation	298,990,000
Construction work in progress	$ 3,359,000
Nameplate capacity (MW) \| MW	3,310
Cleco Power [Member] \| Rodemacher Unit #2 [Member]
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 144,316,000
Accumulated depreciation	75,710,000
Construction work in progress	$ 166,000
Ownership interest percentage (in hundredths)	30.00%
Nameplate capacity (MW) \| MW	523
Ownership interest (MW) \| MW	157
Cleco Power [Member] \| Dolet Hills [Member]
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 394,698,000
Accumulated depreciation	223,280,000
Construction work in progress	$ 3,193,000
Ownership interest percentage (in hundredths)	50.00%
Nameplate capacity (MW) \| MW	650
Ownership interest (MW) \| MW	325
Successor [Member]
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 247,337,000
Accumulated depreciation	7,313,000	$ 0
Construction work in progress	3,359,000
Successor [Member] \| Rodemacher Unit #2 [Member]
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	70,136,000
Accumulated depreciation	1,530,000
Construction work in progress	$ 166,000
Ownership interest percentage (in hundredths)	30.00%
Nameplate capacity (MW) \| MW	523
Ownership interest (MW) \| MW	157
Successor [Member] \| Dolet Hills [Member]
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 177,201,000
Accumulated depreciation	5,783,000
Construction work in progress	$ 3,193,000
Ownership interest percentage (in hundredths)	50.00%
Nameplate capacity (MW) \| MW	650
Ownership interest (MW) \| MW	325

The capacity (in megawatts) of the jointly owned generation unit.

No definition available.

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Namespace Prefix:	cnl_
Data Type:	num:powerItemType
Balance Type:	na
Period Type:	instant

- Definition

The entity's ownership interest in the generation unit's name plate capacity (in megawatts).

+ References

No definition available.

+ Details

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Namespace Prefix:	cnl_
Data Type:	num:powerItemType
Balance Type:	na
Period Type:	instant

- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

+ References

+ Details

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- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

+ Details

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- Details

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- Details

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- Details

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