Fair Value Accounting Instruments - Schedule of Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis (Details) - Measured on a Recurring Basis - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Asset description
Short-term investments	$ 286,707	$ 242,596
Total assets	292,136	250,725
Liability description
Total liabilities	13,043	15,786
CLECO POWER
Asset description
Short-term investments	172,080	169,606
Total assets	177,413	172,693
Liability description
Total liabilities	13,005	15,112
FTRs
Asset description
Derivative assets	881	3,087
Liability description
Derivative liabilities	435	781
FTRs | CLECO POWER
Asset description
Derivative assets	881	3,087
Liability description
Derivative liabilities	435	781
Natural gas derivatives
Asset description
Derivative assets	4,548	5,042
Liability description
Derivative liabilities	12,608	15,005
Natural gas derivatives | CLECO POWER
Asset description
Derivative assets	4,452	0
Liability description
Derivative liabilities	12,570	14,331
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1)
Asset description
Short-term investments	286,707	242,596
Total assets	286,707	242,596
Liability description
Total liabilities	0	0
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1) | CLECO POWER
Asset description
Short-term investments	172,080	169,606
Total assets	172,080	169,606
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
QUOTED PRICES IN ACTIVE MARKETS FOR IDENTICAL ASSETS (LEVEL 1) | Natural gas derivatives | CLECO POWER
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	0	0
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)
Asset description
Short-term investments	0	0
Total assets	4,548	5,042
Liability description
Total liabilities	12,608	15,005
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2) | CLECO POWER
Asset description
Short-term investments	0	0
Total assets	4,452	0
Liability description
Total liabilities	12,570	14,331
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	4,548	5,042
Liability description
Derivative liabilities	12,608	15,005
SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2) | Natural gas derivatives | CLECO POWER
Asset description
Derivative assets	4,452	0
Liability description
Derivative liabilities	12,570	14,331
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)
Asset description
Short-term investments	0	0
Total assets	881	3,087
Liability description
Total liabilities	435	781
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | CLECO POWER
Asset description
Short-term investments	0	0
Total assets	881	3,087
Liability description
Total liabilities	435	781
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | FTRs
Asset description
Derivative assets	881	3,087
Liability description
Derivative liabilities	435	781
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | FTRs | CLECO POWER
Asset description
Derivative assets	881	3,087
Liability description
Derivative liabilities	435	781
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | Natural gas derivatives
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	0	0
SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3) | Natural gas derivatives | CLECO POWER
Asset description
Derivative assets	0	0
Liability description
Derivative liabilities	$ 0	$ 0