Intangible Assets and Liabilities - Schedule of Amortization of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
LTSA
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible liabilities	$ 882	$ 871	$ 2,646	$ 2,323
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible liabilities	871	882	2,613	2,352
Cleco Katrina/Rita right to bill and collect storm recovery charges
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	0	5,660	517	15,702
Cleco Katrina/Rita right to bill and collect storm recovery charges | CLECO POWER
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	0	5,660	517	15,702
Trade name
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	64	64	191	191
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 6,400	$ 6,474	$ 19,200	$ 17,873