Debt - Total Indebtedness (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 16, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Long-term debt due within one year	$ 0		$ (66,497)
Finance leases classified as long-term debt due within one year	0		(925)
Unamortized debt issuance costs	(1,523)		(2,776)
Fair value adjustment	89,942		97,345
Total long-term debt and finance leases, net	2,645,043		3,141,924
Deferred debt issuance costs eliminated as a result of the 2016 Merger	$ 3,900		4,300
Senior notes, 3.17%, due 2024
Debt Instrument [Line Items]
Interest rate		3.17%
Senior notes, 3.250%, due 2025
Debt Instrument [Line Items]
Interest rate	3.25%
Gross debt	$ 0		165,000
Senior notes, 3.743%, due 2026
Debt Instrument [Line Items]
Interest rate	3.743%
Gross debt	$ 360,000		535,000
Senior notes, 3.375%, due 2029
Debt Instrument [Line Items]
Interest rate	3.375%
Gross debt	$ 300,000		300,000
Senior notes, 4.973%, due 2046
Debt Instrument [Line Items]
Interest rate	4.973%
Gross debt	$ 350,000		350,000
Bank term loan, variable rate, due 2024
Debt Instrument [Line Items]
Bank term loan, variable rate	0		66,700
Cleco Power
Debt Instrument [Line Items]
Gross debt	1,700,927		1,765,426
Barge lease obligations	0		12,971
Gross amount of long-term debt and finance leases	1,825,927		1,903,397
Long-term debt due within one year	(264,934)		(189,389)
Finance leases classified as long-term debt due within one year	0		(925)
Unamortized debt discount	(3,866)		(4,178)
Unamortized debt issuance costs	(10,503)		(11,753)
Total long-term debt and finance leases, net	$ 1,546,624		1,697,152
Cleco Power | Senior notes, 3.17%, due 2024
Debt Instrument [Line Items]
Interest rate	3.17%
Gross debt	$ 0		50,000
Cleco Power | Senior notes, 3.68%, due 2025
Debt Instrument [Line Items]
Interest rate	3.68%
Gross debt	$ 75,000		75,000
Cleco Power | Senior notes, 3.47%, due 2026
Debt Instrument [Line Items]
Interest rate	3.47%
Gross debt	$ 130,000		130,000
Cleco Power | Senior notes, 5.96%, due 2026
Debt Instrument [Line Items]
Interest rate	5.96%
Gross debt	$ 100,000		100,000
Cleco Power | Senior notes, 4.33%, due 2027
Debt Instrument [Line Items]
Interest rate	4.33%
Gross debt	$ 50,000		50,000
Cleco Power | Senior notes, 3.57%, due 2028
Debt Instrument [Line Items]
Interest rate	3.57%
Gross debt	$ 200,000		200,000
Cleco Power | Senior notes, 6.50%, due 2035
Debt Instrument [Line Items]
Interest rate	6.50%
Gross debt	$ 295,000		295,000
Cleco Power | Senior notes, 6.00%, due 2040
Debt Instrument [Line Items]
Interest rate	6.00%
Gross debt	$ 250,000		250,000
Cleco Power | Senior notes, 5.12%, due 2041
Debt Instrument [Line Items]
Interest rate	5.12%
Gross debt	$ 100,000		100,000
Cleco Power | Series A GO Zone bonds, 2.50%, due 2038, mandatory tender in 2025
Debt Instrument [Line Items]
Interest rate	2.50%
Gross debt	$ 50,000		50,000
Cleco Power | Series B GO Zone bonds, 4.25%, due 2038
Debt Instrument [Line Items]
Interest rate	4.25%
Gross debt	$ 50,000		50,000
Cleco Power | Cleco Securitization I storm recovery bonds, 4.016%, due 2033
Debt Instrument [Line Items]
Interest rate	4.016%
Gross debt	$ 100,927		115,426
Cleco Power | Cleco Securitization I storm recovery bonds, 4.646%, due 2044
Debt Instrument [Line Items]
Interest rate	4.646%
Gross debt	$ 300,000		300,000
Cleco Power | Bank term loan, variable rate, due 2025
Debt Instrument [Line Items]
Bank term loan, variable rate	125,000		125,000
Cleco Holdings
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (5,400)		$ (7,000)