Variable Interest Entities - Carrying Amount of Assets and Liabilities with Maximum Exposure to Loss (Details) - CLECO POWER - Oxbow - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Variable Interest Entity [Line Items]
Oxbow’s net assets/liabilities	$ 14,645	$ 18,145
Cleco Power’s 50% equity	7,322	9,072
Cleco Power’s maximum exposure to loss	$ 7,322	$ 9,072
Ownership percentage by Cleco Power (in hundredths)	50.00%	50.00%

Amount of net assets (liabilities).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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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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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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