Pension Plan and Employee Benefits - Narrative (Details)		1 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) bonus	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
401(k) one time benefit, percent of employee's gross pay	30.00%	30.00%
401(k) Plan expense, additional cost	$ 200,000
PENSION BENEFITS
Defined Benefit Plan Disclosure [Line Items]
Consecutive calendar years				5 years
Most recent period of employment				10 years
Estimated pension contributions required through 2028				$ 94,200,000
Estimated pension contributions required through 2024				$ 25,700,000
Defined benefit plan, interest crediting rate				5.56%	5.07%
Net actuarial loss (gain) occurring during period				$ 17,082,000	$ (58,124,000)
Net periodic benefit cost				1,856,000	16,056,000	$ 30,391,000
Special/contractual termination benefits, percent increase in benefits	10.00%	10.00%
Special/contractual termination benefits				$ 0	$ 0	$ 3,270,000
Discount rate				5.44%	2.98%	2.74%
Expected return on plan assets				6.60%	5.25%	5.00%
Actual return on plan assets				9.23%	(19.94%)
SERP net actuarial gain				$ (26,300,000)	$ 174,733,000
PENSION BENEFITS | Forecast
Defined Benefit Plan Disclosure [Line Items]
Discount rate			5.13%
Expected return on plan assets			6.68%
Decrease in expected pension costs			$ 1,300,000
PENSION BENEFITS | Support Group
Defined Benefit Plan Disclosure [Line Items]
Special/contractual termination benefits		$ 900,000
PENSION BENEFITS | Other Subsidiaries
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost				1,900,000	3,200,000	$ 4,500,000
PENSION BENEFITS | Cleco Power
Defined Benefit Plan Disclosure [Line Items]
Special/contractual termination benefits		$ 2,400,000
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain) occurring during period				5,110,000	(10,289,000)
Net periodic benefit cost				3,712,000	4,898,000	5,231,000
Special/contractual termination benefits				0	$ 0	$ 0
Assets set aside in a trust				$ 0
Discount rate				5.61%	2.82%	2.39%
Assumed health care cost trend rates for next fiscal year				5.00%
Assumed health care cost trend rates thereafter next fiscal year				5.00%
Ultimate health care trend rate				5.00%
SERP net actuarial gain				$ 5,110,000	$ 10,289,000
Other Postretirement Benefits Plan [Member] | Cleco Power
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost				$ 3,500,000	4,400,000	$ 4,700,000
SERP BENEFITS
Defined Benefit Plan Disclosure [Line Items]
Consecutive calendar years				5 years
Most recent period of employment				60 months
Net actuarial loss (gain) occurring during period				$ (345,000)	(22,097,000)
Net periodic benefit cost				$ 3,468,000	$ 3,740,000	$ 3,783,000
Discount rate				5.46%	2.95%	2.64%
Number of highest cash bonuses | bonus				5
SERP net actuarial gain				$ 345,000	$ 22,097,000
SERP BENEFITS | Cleco Power
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost				$ 500,000	$ 600,000	$ 600,000