Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	$ 3,099,914	$ 2,777,978	$ 2,954,156	$ 2,757,023
Balances, end of period	2,978,446	2,856,380	2,978,446	2,856,380
TOTAL AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(23,615)	(25,168)	(23,629)	(25,796)
Balances, end of period	(23,608)	(25,588)	(23,608)	(25,588)
POSTRETIREMENT BENEFIT NET LOSS
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(23,615)	(25,168)	(23,629)	(25,796)
Amounts reclassified from AOCI	7	(420)	21	208
Balances, end of period	(23,608)	(25,588)	(23,608)	(25,588)
CLECO POWER
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	1,987,930	1,826,826	1,948,537	1,807,879
Balances, end of period	1,991,005	1,854,598	1,991,005	1,854,598
CLECO POWER | TOTAL AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(17,814)	(24,231)	(18,183)	(24,753)
Balances, end of period	(17,444)	(23,880)	(17,444)	(23,880)
CLECO POWER | POSTRETIREMENT BENEFIT NET LOSS
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(12,579)	(18,681)	(12,885)	(19,139)
Amounts reclassified from AOCI	307	287	613	745
Balances, end of period	(12,272)	(18,394)	(12,272)	(18,394)
CLECO POWER | NET LOSS ON CASH FLOW HEDGES
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(5,235)	(5,550)	(5,298)	(5,614)
Amounts reclassified from AOCI	63	64	126	128
Balances, end of period	$ (5,172)	$ (5,486)	$ (5,172)	$ (5,486)