Fair Value Accounting and Financial Instruments - Fair Value of Financial Assets and Liabilities Measured On A Recurring Basis (Details) - Measured on a Recurring Basis - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Asset description
Money market funds	$ 218,259	$ 145,033
Total assets	390,462	239,474
Liability description
Total liabilities	4,959	834
CLECO POWER
Asset description
Money market funds	151,637	82,411
Total assets	156,832	87,926
Liability description
Total liabilities	457	597
FTRs
Asset description
Derivative assets	5,977	6,977
Liability description
Derivative liabilities	3,982	834
FTRs | CLECO POWER
Asset description
Derivative assets	5,195	5,515
Liability description
Derivative liabilities	457	597
Natural gas derivatives
Asset description
Derivative assets	166,226	87,464
Liability description
Derivative liabilities	977	0
Natural gas derivatives | CLECO POWER
Liability description
Derivative liabilities	100
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1)
Asset description
Money market funds	218,259	145,033
Total assets	218,259	145,033
Liability description
Total liabilities	0	0
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1) | CLECO POWER
Asset description
Money market funds	151,637	82,411
Total assets	151,637	82,411
Liability description
Total liabilities	0	0
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1) | FTRs
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	0	0
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1) | FTRs | CLECO POWER
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	0	0
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1) | Natural gas derivatives
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	0	0
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)
Asset description
Money market funds	0	0
Total assets	166,226	87,464
Liability description
Total liabilities	977	0
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2) | CLECO POWER
Asset description
Money market funds	0	0
Total assets	0	0
Liability description
Total liabilities	0	0
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2) | FTRs
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	0	0
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2) | FTRs | CLECO POWER
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	0	0
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2) | Natural gas derivatives
Asset description
Derivative assets	166,226	87,464
Liability description
Derivative liabilities	977	0
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Asset description
Money market funds	0	0
Derivative assets	5,977	6,977
Total assets	5,977	6,977
Liability description
Derivative liabilities	3,982	834
Total liabilities	3,982	834
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | CLECO POWER
Asset description
Money market funds	0	0
Derivative assets	5,195	5,515
Total assets	5,195	5,515
Liability description
Derivative liabilities	457	597
Total liabilities	457	597
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | FTRs
Asset description
Derivative assets	5,977	6,977
Liability description
Derivative liabilities	3,982	834
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | FTRs | CLECO POWER
Asset description
Derivative assets	5,195	5,515
Liability description
Derivative liabilities	457	597
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | Natural gas derivatives
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	$ 0	$ 0