Schedule I Financial Statements of Cleco Holdings (Parent Company Only) - Condensed Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Condensed Statements of Comprehensive Income [Abstract]
Net income	$ 122,300	$ 152,665	$ 94,437
Other comprehensive income (loss), net of tax
Postretirement benefits (loss) gain, net of tax expense (benefit)	(8,283)	(19,299)	5,296
Total other comprehensive (loss) income, net of tax	(8,283)	(19,299)	5,296
Comprehensive income, net of tax	114,017	133,366	99,733
Cleco Holdings
Condensed Statements of Comprehensive Income [Abstract]
Net income	122,300	152,665	94,437
Other comprehensive income (loss), net of tax
Postretirement benefits (loss) gain, net of tax expense (benefit)	(8,283)	(19,299)	5,296
Total other comprehensive (loss) income, net of tax	(8,283)	(19,299)	5,296
Comprehensive income, net of tax	$ 114,017	$ 133,366	$ 99,733