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	Dec. 31, 2021	Dec. 31, 2020
Asset Description
Money market funds	$ 145,033	$ 86,001
Total assets	239,474	99,405
Liability Description
Total liabilities	834	3,237
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1)
Asset Description
Money market funds	145,033	0
Total assets	145,033	0
Liability Description
Total liabilities	0	0
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)
Asset Description
Money market funds	0	86,001
Total assets	87,464	94,600
Liability Description
Total liabilities	0	1,612
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Asset Description
Money market funds	0	0
FTRs and other commodity derivatives	6,977	4,805
Total assets	6,977	4,805
Liability Description
FTRs and other commodity derivatives	834	1,625
Total liabilities	834	1,625
CLECO POWER
Asset Description
Money market funds	82,411	25,357
Total assets	87,926	29,694
Liability Description
Total liabilities	597	1,121
CLECO POWER | QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1)
Asset Description
Money market funds	82,411	0
Total assets	82,411	0
Liability Description
Total liabilities	0	0
CLECO POWER | SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)
Asset Description
Money market funds	0	25,357
Total assets	0	25,357
Liability Description
Total liabilities	0	0
CLECO POWER | SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Asset Description
Money market funds	0	0
FTRs and other commodity derivatives	5,515	4,337
Total assets	5,515	4,337
Liability Description
FTRs and other commodity derivatives	597	1,121
Total liabilities	597	1,121
Financial Transmission Right
Asset Description
FTRs and other commodity derivatives	6,977	4,805
Liability Description
FTRs and other commodity derivatives	834	1,625
Financial Transmission Right | QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1)
Asset Description
FTRs and other commodity derivatives	0	0
Liability Description
FTRs and other commodity derivatives	0	0
Financial Transmission Right | SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)
Asset Description
FTRs and other commodity derivatives	0	0
Liability Description
FTRs and other commodity derivatives	0	0
Financial Transmission Right | SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Asset Description
FTRs and other commodity derivatives	6,977	4,805
Liability Description
FTRs and other commodity derivatives	834	1,625
Financial Transmission Right | CLECO POWER
Asset Description
FTRs and other commodity derivatives	5,515	4,337
Liability Description
FTRs and other commodity derivatives	597	1,121
Financial Transmission Right | CLECO POWER | QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1)
Asset Description
FTRs and other commodity derivatives	0	0
Liability Description
FTRs and other commodity derivatives	0	0
Financial Transmission Right | CLECO POWER | SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)
Asset Description
FTRs and other commodity derivatives	0	0
Liability Description
FTRs and other commodity derivatives	0	0
Financial Transmission Right | CLECO POWER | SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Asset Description
FTRs and other commodity derivatives	5,515	4,337
Liability Description
FTRs and other commodity derivatives	597	1,121
Natural gas derivatives
Asset Description
FTRs and other commodity derivatives	87,464	8,599
Liability Description
FTRs and other commodity derivatives	0	1,612
Natural gas derivatives | QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1)
Asset Description
FTRs and other commodity derivatives	0	0
Liability Description
FTRs and other commodity derivatives	0	0
Natural gas derivatives | SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)
Asset Description
FTRs and other commodity derivatives	87,464	8,599
Liability Description
FTRs and other commodity derivatives	0	1,612
Natural gas derivatives | SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Asset Description
FTRs and other commodity derivatives	0	0
Liability Description
FTRs and other commodity derivatives	$ 0	$ 0