Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Asset Retirement Obligation (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)
Loss Contingencies [Line Items]
Revisions and adjustments		$ 48,641
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance		28,022
Liabilities settled		(1,316)
Accretion		715
Revisions and adjustments		48,641
Ending balance	$ 76,062	76,062
CLECO POWER
Loss Contingencies [Line Items]
Revisions and adjustments	13,100	13,101
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance		11,364
Liabilities settled		0
Accretion		249
Revisions and adjustments	13,100	13,101
Ending balance	24,714	24,714
Cleco Cajun
Loss Contingencies [Line Items]
Revisions and adjustments	35,500	35,540
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance		16,658
Liabilities settled		(1,316)
Accretion		466
Revisions and adjustments	35,500	35,540
Ending balance	51,348	51,348
Indemnification assets, maximum environmental costs	25,000	25,000
Indemnification assets	22,100	22,100
Indemnification assets, current	1,100	1,100
Indemnification assets, noncurrent	$ 21,000	$ 21,000

Recorded Third-Party Environmental Recoveries, Maximum Costs

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

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-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

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Cumulative amount of the asset for third-party recoveries related to environmental remediation obligations that is recoverable within one year of the balance sheet date.

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Present value of the asset for third-party recoveries related to environmental remediation obligations as of the balance sheet date (if the receivable is discounted).

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Cumulative amount of the asset for third-party recoveries related to environmental remediation obligations that is recoverable after one year from the balance sheet date.

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