Intangible Assets and Liabilities - Schedule of Amortization of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
LTSA
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible liabilities	$ 871	$ 871	$ 1,742	$ 1,742
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible liabilities	718	882	1,600	1,764
Cleco Katrina/Rita right to bill and collect storm recovery charges
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	0	0	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	0	0	517
Trade name
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	64	64	128	128
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 6,400	$ 6,400	$ 12,800	$ 12,800