Intangible Assets and Liabilities - Schedule of Amortization of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
LTSA
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible liabilities	$ 871	$ 871
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible liabilities	882	882
Cleco Katrina/Rita right to bill and collect storm recovery charges
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	0	517
Cleco Katrina/Rita right to bill and collect storm recovery charges | CLECO POWER
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	0	517
Trade name
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	64	64
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 6,400	$ 6,400