Guarantor Obligations, Collateral Held Directly Or By Third Parties, Amount

No definition available.

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Namespace Prefix:	cnl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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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Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Details

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- Details

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Balance Type:
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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
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Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Off-Balance Sheet Commitments and Guarantees (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	May 31, 2020
Guarantor Obligations [Line Items]
Guarantor obligations, collateral held directly or by third parties, amount	$ 0
Performance Guarantee
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	42,400,000
Indemnification Agreement
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	40,000,000.0
Indemnification Agreement including fundamental organizational structure
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	400,000,000.0
CLECO POWER
Guarantor Obligations [Line Items]
Guarantor obligations, collateral held directly or by third parties, amount	0
CLECO POWER \| Indemnification Agreement
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	40,000,000.0
CLECO POWER \| Indemnification Agreement including fundamental organizational structure
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	400,000,000.0
CLECO POWER \| Financial Guarantee
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 83,000,000.0
CLECO HOLDINGS \| Letters of Credit
Guarantor Obligations [Line Items]
Letters of credit		$ 1,300,000	$ 34,500,000