The Company (Details) customer in Thousands	Dec. 31, 2019 generation customer entity generation_unit MW
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of transmission interconnection facility subsidiaries \| entity	2
CLECO POWER
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of generating units owned \| generation	10
Nameplate capacity of all generating units (MW)	3,360
Approximate number of customers served \| customer	288
Ownership interest in lignite entity	50.00%
Cleco Cajun
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of generating units owned \| generation_unit	8
Nameplate capacity of all generating units (MW)	3,555

The approximate number of customers served by Cleco Power, a regulated electric utility company.

No definition available.

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- Definition

Total nameplate capacity (in megawatts) of all generating units.

+ References

No definition available.

+ Details

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Namespace Prefix:	cnl_
Data Type:	num:powerItemType
Balance Type:	na
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- Definition

Number of Generation Units Owned

+ References

No definition available.

+ Details

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- Definition

The number of transmission interconnection facility subsidiaries that are classified as other segments by the Entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	cnl_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ 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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- Details

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Namespace Prefix:
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- Details

Name:	dei_LegalEntityAxis=cnl_ClecoCajunMember
Namespace Prefix:
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