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Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Risks and Uncertainties (Details) - CLECO POWER - USD ($) $ in Millions	1 Months Ended
	Jun. 30, 2020	Sep. 30, 2020
Oxbow
Loss Contingencies [Line Items]
Costs to be billed		$ 0.3
Dolet Hills Power Station
Loss Contingencies [Line Items]
Increase in ARO liabilities	$ 3.3
Investment balance		156.2
Dolet Hills Power Station \| DHLC
Loss Contingencies [Line Items]
Costs to be billed		163.5
Oxbow \| Oxbow
Loss Contingencies [Line Items]
Costs to be billed		$ 10.4