Jointly Owned Generation Units (Details) $ in Thousands	Dec. 31, 2021 USD ($) MW
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 142,600
Accumulated depreciation	29,799
Construction work in progress	874
RODEMACHER UNIT 2
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	83,675
Accumulated depreciation	19,783
Construction work in progress	$ 400
Ownership interest percentage	30.00%
Rated capacity (MW) \| MW	523
Ownership interest (MW) \| MW	157
BAYOU COVE
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 41,435
Accumulated depreciation	6,809
Construction work in progress	$ 0
Ownership interest percentage	75.00%
Rated capacity (MW) \| MW	300
Ownership interest (MW) \| MW	225
BIG CAJUN II, UNIT 3
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 17,490
Accumulated depreciation	3,207
Construction work in progress	$ 474
Ownership interest percentage	58.00%
Rated capacity (MW) \| MW	588
Ownership interest (MW) \| MW	341
CLECO POWER \| RODEMACHER UNIT 2
Jointly Owned Utility Plant Interests [Line Items]
Utility plant in service	$ 157,855
Accumulated depreciation	93,963
Construction work in progress	$ 400
Ownership interest percentage	30.00%
Rated capacity (MW) \| MW	523
Ownership interest (MW) \| MW	157

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

No definition available.

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Data Type:	dtr-types: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:	dtr-types: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://fasb.org/us-gaap/role/ref/legacyRef
-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=122136288&loc=d3e659983-123033

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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_
Data Type:	xbrli:monetaryItemType
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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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type: