Summary of Significant Accounting Policies - Revisions Previously Issued Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended		9 Months Ended	12 Months Ended
	Mar. 31, 2025	Jun. 30, 2025	Jun. 30, 2024	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	$ 5,546	$ 11,656	$ 13,694	$ 29,463	$ 38,944	$ 36,356	$ 18,020
Accounts receivable	632		24,916	6,508	26,712	14,792	(53,044)
Customer deposits	407	760	802	872	1,261	(1,369)	(2,026)
Other deferred accounts	(6,544)	(4,967)	(2,043)	(20,447)	(7,122)	(10,969)	(3,420)
Other deferred accounts			(12,513)
Accounts payable	12,119	925	4,466	49,074	39,419	60,340	(13,637)
Accounts payable			(30,690)
Taxes accrued	6,732	16,426	81,062	60,950	39,636	518	11,701
Other operating	(19,558)	(5,737)	(1,473)	(16,082)	(5,333)	874	(13,655)
Other operating			(10,147)
Net cash provided by operating activities	55,254	67,046	176,058	257,715	285,719	415,890	349,184
Additions to property, plant, and equipment	(69,101)	(141,470)	(123,812)	(190,676)	(274,247)	(263,824)	(248,691)
Customer advances for construction	900	1,236	8,527	17,834	18,058	31,888	7,652
Net cash (used in) provided by investing activities	(70,978)	(142,605)	349,973	292,962	220,575	(229,514)	(197,529)
Credit deposits		0	7,750	7,750	7,750	7,000	15,267
Net cash provided by (used in) financing activities		124,554	(362,705)	(432,161)	(599,478)	(121,881)
Accrued additions to property, plant, and equipment	9,114	12,495	8,843	7,532	11,470	8,533
Storm reserve		(9,909)	(10,470)
Incentive compensation payable		35,496	34,388
Postretirement benefit obligations		19,624	1,599
Regulatory assets		(50,458)			(295,125)
AS REPORTED
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	435		3,685	5,875	8,774	10,102	5,502
Accounts receivable	(710)		21,816	1,612	20,319	8,112	(61,848)
Customer deposits	1,749		3,902	5,768	7,654	5,311	6,778
Other deferred accounts	(19,419)			(10,824)	2,943	(1,632)	(7,333)
Other deferred accounts			(3,236)
Accounts payable	9,105			30,560	11,856	37,827	(20,711)
Accounts payable			(20,239)
Taxes accrued	7,226		80,585	60,424	39,010	225	11,337
Other operating	(5,892)			(12,684)	(1,079)	874	(8,205)
Other operating			(10,409)
Net cash provided by operating activities	54,442		185,038	265,136	296,805	421,192	344,912
Additions to property, plant, and equipment	(68,289)		(116,515)	(172,513)	(259,525)	(230,238)	(236,767)
Customer advances for construction	900		0	0	0	0	0
Net cash (used in) provided by investing activities	(70,166)		348,743	293,291	217,239	(227,816)	(193,257)
Credit deposits			0	0	0	0	10,247
Net cash provided by (used in) financing activities			(370,455)	(439,911)	(607,228)	(128,881)
Accrued additions to property, plant, and equipment	3,466		4,131	4,488	5,010	5,052
REVISION
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	5,111		10,009	23,588	30,170	26,254	12,518
Accounts receivable	1,342		3,100	4,896	6,393	6,680	8,804
Customer deposits	(1,342)		(3,100)	(4,896)	(6,393)	(6,680)	(8,804)
Other deferred accounts	12,875			(9,623)	(10,065)	(9,337)	3,913
Other deferred accounts			(9,277)
Accounts payable	3,014			18,514	27,563	22,513	7,074
Accounts payable			(10,451)
Taxes accrued	(494)		477	526	626	293	364
Other operating	(13,666)			(3,398)	(4,254)	0	(5,450)
Other operating			262
Net cash provided by operating activities	812		(8,980)	(7,421)	(11,086)	(5,302)	4,272
Additions to property, plant, and equipment	(812)		(7,297)	(18,163)	(14,722)	(33,586)	(11,924)
Customer advances for construction	0		8,527	17,834	18,058	31,888	7,652
Net cash (used in) provided by investing activities	(812)		1,230	(329)	3,336	(1,698)	(4,272)
Credit deposits			7,750	7,750	7,750	7,000	5,020
Net cash provided by (used in) financing activities			7,750	7,750	7,750	7,000
Accrued additions to property, plant, and equipment	5,648		4,712	3,044	6,460	3,481
Revision of Prior Period, Reclassification, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other deferred accounts			10,400
Accounts payable			26,200
Storm reserve			10,400
Incentive compensation payable			26,200
Revision of Prior Period, Reclassification, Other Operating Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Incentive compensation payable			8,200
Provision for credit losses			500
CLECO POWER
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	4,673	9,139	6,519	14,337	18,910	17,039	5,258
Accounts receivable	345		6,011	(12,509)	5,016	24,724	(39,549)
Customer deposits	407	760	802	872	1,261	(1,369)	(2,026)
Other deferred accounts	(3,997)	97	1,504	(14,210)	1,130	(3,665)	(1,682)
Other deferred accounts			(8,966)
Accounts payable	3,208			31,115	22,959	31,805	962
Accounts payable			(10,830)
Taxes accrued	13,898	26,438	34,828	23,554	(11,744)	6,607	9,784
Other operating	(10,507)	(5,374)	(4,478)	(3,011)	1,097	417	(6,704)
Other operating			(7,507)
Net cash provided by operating activities	77,152	110,147	151,261	241,434	259,499	394,635	278,537
Additions to property, plant, and equipment	(68,644)	(141,430)	(120,378)	(186,691)	(270,058)	(254,562)	(240,864)
Customer advances for construction	900	1,236	8,527	17,834	18,058	31,888	7,652
Net cash (used in) provided by investing activities	(70,521)	(142,565)	(110,362)	(166,822)	(239,005)	(220,349)	(224,965)
Credit deposits		0	7,750	7,750	7,750	7,000	14,974
Net cash provided by (used in) financing activities		84,554	(41,005)	(77,956)	(42,971)	(143,352)
Accrued additions to property, plant, and equipment	9,097	12,477	8,798	7,530	11,470	7,677
Storm reserve		(9,909)	(10,470)
Incentive compensation payable		18,278	9,462
Postretirement benefit obligations		18,269	681
Regulatory assets		(42,843)			(287,390)
CLECO POWER | AS REPORTED
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	1,317		0	1,236	1,867	1,661	0
Accounts receivable	(997)		2,911	(17,405)	(1,377)	18,044	(48,353)
Customer deposits	1,749		3,902	5,768	7,654	5,311	6,778
Other deferred accounts	(7,542)			(5,128)	10,564	4,441	(2,281)
Other deferred accounts			(694)
Accounts payable	1,338			20,575	5,295	19,185	854
Accounts payable			(5,019)
Taxes accrued	13,975		34,900	23,473	(11,845)	6,567	9,704
Other operating	(6,365)			(2,030)	2,229	417	(5,148)
Other operating			(6,163)
Net cash provided by operating activities	76,340		160,241	248,855	270,585	399,943	274,265
Additions to property, plant, and equipment	(67,832)		(113,081)	(168,528)	(255,336)	(220,982)	(228,940)
Customer advances for construction	900		0	0	0	0	0
Net cash (used in) provided by investing activities	(69,709)		(111,592)	(166,493)	(242,341)	(218,657)	(220,693)
Credit deposits			0	0	0	0	9,954
Net cash provided by (used in) financing activities			(48,755)	(85,706)	(50,721)	(150,352)
Accrued additions to property, plant, and equipment	3,449		4,086	4,486	5,010	4,196
CLECO POWER | REVISION
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Unearned compensation expense	3,356		6,519	13,101	17,043	15,378	5,258
Accounts receivable	1,342		3,100	4,896	6,393	6,680	8,804
Customer deposits	(1,342)		(3,100)	(4,896)	(6,393)	(6,680)	(8,804)
Other deferred accounts	3,545			(9,082)	(9,434)	(8,106)	599
Other deferred accounts			(8,272)
Accounts payable	1,870			10,540	17,664	12,620	108
Accounts payable			(5,811)
Taxes accrued	(77)		(72)	81	101	40	80
Other operating	(4,142)			(981)	(1,132)	0	(1,556)
Other operating			(1,344)
Net cash provided by operating activities	812		(8,980)	(7,421)	(11,086)	(5,308)	4,272
Additions to property, plant, and equipment	(812)		(7,297)	(18,163)	(14,722)	(33,580)	(11,924)
Customer advances for construction	0		8,527	17,834	18,058	31,888	7,652
Net cash (used in) provided by investing activities	(812)		1,230	(329)	3,336	(1,692)	(4,272)
Credit deposits			7,750	7,750	7,750	7,000	$ 5,020
Net cash provided by (used in) financing activities			7,750	7,750	7,750	7,000
Accrued additions to property, plant, and equipment	$ 5,648		4,712	$ 3,044	$ 6,460	$ 3,481
CLECO POWER | Revision of Prior Period, Reclassification, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other deferred accounts			10,400
Storm reserve			10,400
Incentive compensation payable			7,900
CLECO POWER | Revision of Prior Period, Reclassification, Other Operating Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts payable			7,900
Incentive compensation payable			1,500
Provision for credit losses			500
Postretirement benefit obligations		$ 700
Regulatory assets			$ 300