Regulatory Assets and Liabilities - Narrative (Details)					1 Months Ended		3 Months Ended		12 Months Ended
	Jul. 01, 2024 USD ($)	Jun. 30, 2024 USD ($)	Apr. 19, 2024 USD ($)	Apr. 13, 2016 instrument	Sep. 30, 2022 USD ($)	Jul. 31, 2022 MW	Sep. 30, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2011 USD ($) treasury_rate_lock	Jul. 01, 2025 USD ($)	Nov. 20, 2024	Dec. 31, 2022	Dec. 31, 2021	Jul. 01, 2021	Dec. 31, 2016 USD ($)	Dec. 31, 2014	Dec. 31, 2010
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Liability and regulatory asset									$ 9,372,000	$ 5,397,000	$ (7,592,000)
Provision for customer refund									20,900,000	20,510,000
Electric customer credits									0	1,300,000	58,700,000
Treasury Lock
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Number of instruments settled | instrument				2
LPSC | Excess ADIT
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory liability									182,400,000	189,600,000
Dolet Hills | LPSC
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Decrease in regulatory assets								$ 40,000,000.0
Financing costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									5,873,000	6,217,000
Postretirement costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									5,473,000	7,461,000
Louisiana Tax Amendment
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset, amortization amount									33,300,000
Cleco Power
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Liability and regulatory asset									11,784,000	7,384,000	(5,604,000)
Decrease in regulatory assets										64,900,000
Regulatory asset									308,906,000	498,883,000
Regulatory liability									119,499,000	86,005,000
Solar electric generation facility capacity | MW						240
Provision for customer refund									20,900,000	20,510,000
Electric customer credits									0	1,300,000	$ 58,700,000
Cleco Power | IICR
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Public utilities, adjustment provided to residential customer														$ 3,000,000.0
Billing settlement credit, accrual							$ 3,000,000.0
Cleco Power | Treasury Lock
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Number of treasury locks | treasury_rate_lock													2
Loss on sale of derivatives													$ 26,800,000
Cleco Power | Interest Rate Swap
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Loss on sale of derivatives												$ 3,300,000
Cleco Power | Storm reserve
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory liability									69,440,000	76,178,000
Storm reserve balance									69,400,000	76,200,000
Accumulated restoration costs									37,800,000	(43,300,000)
Cleco Power | Residential revenue decoupling
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory liability									4,500,000	3,000,000
Increase (decrease) in regulatory liabilities	$ 3,000,000.0
Cleco Power | Northlake Transmission Agreement
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Liability and regulatory asset									2,000,000.0
Cleco Power | AROs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Liability and regulatory asset							$ 8,600,000
Cleco Power | LPSC | Excess ADIT
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory liability									182,400,000	189,600,000
Cleco Power | Dolet Hills | LPSC
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Decrease in regulatory assets		$ (12,300,000)	$ 40,000,000.0					$ 40,000,000.0
Cleco Power | Acadia Unit 1 acquisition costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																					30 years
Regulatory asset									1,490,000	1,596,000
Cleco Power | Accumulated deferred fuel
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Increase in regulatory assets									$ 22,500,000
Regulated total fuel cost, percentage									98.00%
Regulatory asset									$ 22,910,000	457,000
Cleco Power | Affordability study
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																	10 years
Regulatory asset									7,581,000	8,959,000
Cleco Power | AMI deferred revenue requirement
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																				11 years
Regulatory asset									0	409,000
Cleco Power | Coughlin transaction costs | Coughlin transaction costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																				35 years
Regulatory asset									722,000	753,000
Cleco Power | Production operations and maintenance expenses
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									14,809,000	4,939,000
Cleco Power | Production operations and maintenance expenses | Dolet Hills | LPSC
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period											25 years					20 years
Cleco Power | Dolet Hills carrying charge | Dolet Hills
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period															1 year
Regulatory asset									2,957,000	4,729,000
Cleco Power | Financing costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									5,347,000	5,717,000
Cleco Power | Financing costs | Treasury Lock
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset													$ 7,400,000
Cleco Power | Financing costs | Interest Rate Swap
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset												$ 2,900,000
Cleco Power | Madison Unit 3 property taxes
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									15,350,000	14,196,000
Cleco Power | Northlake Transmission Agreement
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									$ 4,587,000	2,542,000
Cleco Power | Postretirement costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period									5 years
Regulatory asset									$ 51,451,000	58,089,000
Cleco Power | Production O&M Expenses
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period									3 years
Regulatory asset									$ 12,600,000	2,000,000.0
Retail jurisdictional portion									29,700,000
Cleco Power | Production O&M Expenses | Maximum
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									25,000,000.0
Cleco Power | St. Mary Clean Energy Center
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																		4 years
Regulatory asset									0	870,000
Cleco Power | St. Mary Clean Energy Center | LPSC
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset					$ 3,800,000
Provision for customer refund					10,400,000
Electric customer credits					$ 6,600,000
Cleco Power | Training costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																					50 years
Regulatory asset									5,306,000	5,462,000
Cleco Power | Tree trimming costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									0	943,000
Maximum amount of costs approved to defer																			$ 11,000,000.0
Cleco Power | Other Deferred Costs, Primarily Base Rate Case
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																		3 years
Regulatory asset									2,000,000.0	4,500,000
Cleco Power | Coughlin Pipeline Project, Deferred Revenue
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory assets amortization period																		4 years
Regulatory asset										700,000
Cleco Power | Louisiana Tax Amendment
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset		$ 5,500,000
Cleco Power | Industrial Tax Exemption Program
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									2,000,000.0	600,000
Cleco Power | Transmission And Distribution System
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									5,900,000	4,600,000
Cleco Power | Lignite Mine closure costs | Deferred lignite and mine closure costs
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset									$ 0	136,800,000
Cleco Power | Dolet Hills Power Station closure costs | Dolet Hills
Schedule of Regulatory Assets and Liabilities, Net [Line Items]
Regulatory asset										$ 122,200,000