Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	$ 2,889,530	$ 2,978,446	$ 2,947,067	$ 2,954,156
Balances, end of period	3,015,220	2,960,078	3,015,220	2,960,078
TOTAL AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(786)	(23,608)	59	(23,629)
Balances, end of period	(1,208)	(23,598)	(1,208)	(23,598)
POSTRETIREMENT BENEFIT NET LOSS
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(786)	(23,608)	59	(23,629)
Amounts reclassified from AOCI	(422)	10	(1,267)	31
Balances, end of period	(1,208)	(23,598)	(1,208)	(23,598)
CLECO POWER
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	2,064,486	1,991,005	2,022,912	1,948,537
Balances, end of period	2,130,559	1,978,608	2,130,559	1,978,608
CLECO POWER | TOTAL AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(8,047)	(17,444)	(8,365)	(18,183)
Balances, end of period	(7,888)	(17,074)	(7,888)	(17,074)
CLECO POWER | POSTRETIREMENT BENEFIT NET LOSS
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(3,126)	(12,272)	(3,318)	(12,885)
Amounts reclassified from AOCI	97	307	289	920
Balances, end of period	(3,029)	(11,965)	(3,029)	(11,965)
CLECO POWER | NET LOSS ON CASH FLOW HEDGES
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(4,921)	(5,172)	(5,047)	(5,298)
Amounts reclassified from AOCI	62	63	188	189
Balances, end of period	$ (4,859)	$ (5,109)	$ (4,859)	$ (5,109)