Summary of Significant Accounting Policies - Revisions Previously Issued Financial Statements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	$ 30,312	$ 38,944	$ 36,356
Accounts receivable		26,712
Customer deposits	834	1,261	(1,369)
Other deferred accounts		(7,122)	(10,969)
Accounts payable		(39,419)	(60,340)
Taxes accrued	11,931	39,636	518
Other operating		(5,333)	874
Net cash provided by operating activities	275,833	285,719	415,890
Additions to property, plant, and equipment	(348,862)	(274,247)	(263,824)
Customer advances for construction	7,191	18,058	31,888
Net cash (used in) provided by investing activities	(342,209)	220,575	(229,514)
Credit deposits	0	7,750	7,000
Net cash provided by (used in) financing activities	246,783	(599,478)	(121,881)
Accrued additions to property, plant, and equipment	22,163	11,470	8,533
Nonrelated Party
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts receivable	(33,272)	26,712	14,792
AS REPORTED
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense		8,774	10,102
Accounts receivable		20,319
Customer deposits		7,654	5,311
Other deferred accounts		2,943	(1,632)
Accounts payable		(11,856)	(37,827)
Taxes accrued		39,010	225
Other operating		(1,079)	874
Net cash provided by operating activities		296,805	421,192
Additions to property, plant, and equipment		(259,525)	(230,238)
Customer advances for construction		0	0
Net cash (used in) provided by investing activities		217,239	(227,816)
Credit deposits		0	0
Net cash provided by (used in) financing activities		(607,228)	(128,881)
Accrued additions to property, plant, and equipment		5,010	5,052
AS REPORTED | Nonrelated Party
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts receivable			8,112
REVISION
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense		30,170	26,254
Accounts receivable		6,393
Customer deposits		(6,393)	(6,680)
Other deferred accounts		(10,065)	(9,337)
Accounts payable		(27,563)	(22,513)
Taxes accrued		626	293
Other operating		(4,254)	0
Net cash provided by operating activities		(11,086)	(5,302)
Additions to property, plant, and equipment		(14,722)	(33,586)
Customer advances for construction		18,058	31,888
Net cash (used in) provided by investing activities		3,336	(1,698)
Credit deposits		7,750	7,000
Net cash provided by (used in) financing activities		7,750	7,000
Accrued additions to property, plant, and equipment		6,460	3,481
REVISION | Nonrelated Party
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts receivable			6,680
Revision of Prior Period, Reclassification, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Incentive compensation payable		26,300	26,200
Revision of Prior Period, Reclassification, Other Operating Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Incentive compensation payable		8,200	5,100
Cleco Power
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	18,105	18,910	17,039
Accounts receivable		5,016
Customer deposits	834	1,261	(1,369)
Other deferred accounts		1,130	(3,665)
Accounts payable		(22,959)	(31,805)
Taxes accrued	21,791	(11,744)	6,607
Other operating		1,097	417
Net cash provided by operating activities	333,862	259,499	394,635
Additions to property, plant, and equipment	(348,530)	(270,058)	(254,562)
Customer advances for construction	7,191	18,058	31,888
Net cash (used in) provided by investing activities	(341,877)	(239,005)	(220,349)
Credit deposits	0	7,750	7,000
Net cash provided by (used in) financing activities	186,783	(42,971)	(143,352)
Accrued additions to property, plant, and equipment	22,149	11,470	7,677
Incentive compensation payable	18,316	9,462	9,047
Cleco Power | Nonrelated Party
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts receivable	$ (28,269)	5,016	24,724
Cleco Power | AS REPORTED
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense		1,867	1,661
Accounts receivable		(1,377)
Customer deposits		7,654	5,311
Other deferred accounts		10,564	4,441
Accounts payable		(5,295)	(19,185)
Taxes accrued		(11,845)	6,567
Other operating		2,229	417
Net cash provided by operating activities		270,585	399,943
Additions to property, plant, and equipment		(255,336)	(220,982)
Customer advances for construction		0	0
Net cash (used in) provided by investing activities		(242,341)	(218,657)
Credit deposits		0	0
Net cash provided by (used in) financing activities		(50,721)	(150,352)
Accrued additions to property, plant, and equipment		5,010	4,196
Cleco Power | AS REPORTED | Nonrelated Party
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts receivable			18,044
Cleco Power | REVISION
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense		17,043	15,378
Accounts receivable		6,393
Customer deposits		(6,393)	(6,680)
Other deferred accounts		(9,434)	(8,106)
Accounts payable		(17,664)	(12,620)
Taxes accrued		101	40
Other operating		(1,132)	0
Net cash provided by operating activities		(11,086)	(5,308)
Additions to property, plant, and equipment		(14,722)	(33,580)
Customer advances for construction		18,058	31,888
Net cash (used in) provided by investing activities		3,336	(1,692)
Credit deposits		7,750	7,000
Net cash provided by (used in) financing activities		7,750	7,000
Accrued additions to property, plant, and equipment		6,460	3,481
Cleco Power | REVISION | Nonrelated Party
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts receivable			6,680
Cleco Power | Revision of Prior Period, Reclassification, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Incentive compensation payable		7,900	7,900
Cleco Power | Revision of Prior Period, Reclassification, Other Operating Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Incentive compensation payable		$ 1,500	$ 1,100