Allegations By Plaintiff, Failure To Perform

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Estimated Refund Interest Amount

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Loss Contingency, Number Of Findings

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Loss Contingency, Number Of Recommendations

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Number of actions filed in a legal matter.

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Public Utilities, Proposed Return on Equity, Percentage

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The amount of indemnification assets (amounts to be reimbursed if and when certain assumed liabilities are paid) recognized at the acquisition date of a business combination.

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The amount, measured at acquisition-date fair value, of all liabilities assumed that arise from contingencies and were recognized by the entity.

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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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Fuel costs incurred that are directly related to goods produced and sold and services rendered during the reporting 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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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Percentage of public utility's approved return on equity.

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Percentage of public utility's requested rate increase (decrease) with regulatory agency.

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Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Litigation (Details) $ in Millions				1 Months Ended						3 Months Ended	24 Months Ended	30 Months Ended
	Jun. 01, 2020	May 21, 2020	Jan. 01, 2020	Mar. 31, 2020 USD ($)	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2015 USD ($)	Dec. 31, 2014 claim	Nov. 30, 2014 claim	Mar. 31, 2021 USD ($)	Dec. 31, 2019 USD ($)	May 31, 2016 complaint	Sep. 27, 2019 recommendation finding	Feb. 04, 2019 USD ($)
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss										$ 4.5
South Central Generating
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss										1.5
Indemnification asset														$ 10.0
Contingent liability														$ 10.0
FERC
Loss Contingencies [Line Items]
Estimated refund interest amount										1.0
FERC \| MISO Transmission Rates
Loss Contingencies [Line Items]
Public utilities, requested rate increase (decrease), percentage (in hundredths)									0.50%
Gulf Coast Spinning start up costs
Loss Contingencies [Line Items]
Allegations by plaintiff, failure to perform							$ 6.5
Gulf Coast Spinning construction of cotton spinning facility
Loss Contingencies [Line Items]
Allegations by plaintiff, failure to perform							$ 60.0
Actions filed in the 9th Judicial District Court \| Alleged Breach of Fiduciary Duties
Loss Contingencies [Line Items]
Number of actions filed \| claim									4
Actions filed in the Civil District Court \| Alleged Breach of Fiduciary Duties
Loss Contingencies [Line Items]
Number of actions filed \| claim								3	3
CLECO POWER \| LPSC 2018-2019 Fuel Audit
Loss Contingencies [Line Items]
Fuel expense											$ 565.8
CLECO POWER \| MISO Transmission Rates
Loss Contingencies [Line Items]
Public utilities, proposed return on equity, percentage (in hundredths)	10.52%		10.38%		10.32%	9.70%
CLECO POWER \| LPSC
Loss Contingencies [Line Items]
Environmental expense				$ 26.2
CLECO POWER \| FERC
Loss Contingencies [Line Items]
Number of findings \| finding													12
Number of recommendations \| recommendation													59
Estimated refund interest amount										1.0
Loss contingency, estimate of possible loss										$ 0.6
CLECO POWER \| FERC \| MISO Transmission Rates
Loss Contingencies [Line Items]
Number of actions filed \| complaint												2
Public utilities, approved return on equity, percentage (In hundredths)												12.38%
Public utilities, proposed return on equity, percentage (in hundredths)		10.02%			9.88%							6.68%