Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	$ 2,954,156	$ 2,757,023
Balances, end of period	3,099,914	2,777,978
TOTAL AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(23,629)	(25,796)
Balances, end of period	(23,615)	(25,168)
POSTRETIREMENT BENEFIT NET LOSS
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(23,629)	(25,796)
Amounts reclassified from AOCI	14	628
Balances, end of period	(23,615)	(25,168)
CLECO POWER
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	1,948,537	1,807,879
Balances, end of period	1,987,930	1,826,826
CLECO POWER | TOTAL AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(18,183)	(24,753)
Balances, end of period	(17,814)	(24,231)
CLECO POWER | POSTRETIREMENT BENEFIT NET LOSS
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(12,885)	(19,139)
Amounts reclassified from AOCI	306	458
Balances, end of period	(12,579)	(18,681)
CLECO POWER | NET LOSS ON CASH FLOW HEDGES
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances, beginning of period	(5,298)	(5,614)
Amounts reclassified from AOCI	63	64
Balances, end of period	$ (5,235)	$ (5,550)