Fair Value Accounting - Significant Unobservable Inputs Used in Developing Fair Value of Level 3 Positions (Details) - Measured on a Recurring Basis - Level 3 $ in Thousands	Mar. 31, 2021 USD ($) $ / MW	Dec. 31, 2020 USD ($) $ / MW
FAIR VALUE
ASSETS | $	$ 2,140	$ 4,805
LIABILITIES | $	1,117	1,625
CLECO POWER
FAIR VALUE
ASSETS | $	1,986	4,337
LIABILITIES | $	$ 898	$ 1,121
Minimum
FAIR VALUE
FORWARD PRICE RANGE (usd per mwh) | $ / MW	(1.18)	(3.49)
Minimum | CLECO POWER
FAIR VALUE
FORWARD PRICE RANGE (usd per mwh) | $ / MW	(1.18)	(3.34)
Maximum
FAIR VALUE
FORWARD PRICE RANGE (usd per mwh) | $ / MW	4.09	4.36
Maximum | CLECO POWER
FAIR VALUE
FORWARD PRICE RANGE (usd per mwh) | $ / MW	4.09	4.36