Fair Value Accounting - Narrative (Details) MWh in Millions, MMBTU in Millions	12 Months Ended
	Dec. 31, 2020 MWh	Dec. 31, 2020 MMBTU	Dec. 31, 2019 MWh	Dec. 31, 2019 MMBTU
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Volume outstanding (MWh / MMBtu)	15.3	73.0	14.6	58.5
CLECO POWER
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Volume outstanding (MWh / MMBtu)	9.5		9.2