Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Risks and Uncertainties (Details) - CLECO POWER - USD ($) $ in Millions	1 Months Ended
Jun. 30, 2020	Jun. 30, 2021
Dolet Hills Power Station
Loss Contingencies [Line Items]
Increase in ARO liabilities	$ 3.3
Investment balance		$ 62.6
Dolet Hills Power Station \| DHLC
Loss Contingencies [Line Items]
Costs to be billed		96.1
Oxbow \| Oxbow
Loss Contingencies [Line Items]
Costs to be billed		$ 6.6

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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