Intangible Assets and Liabilities - Schedule of Finite-Lived Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Total intangible assets carrying amount	$ 259,698	$ 259,698
Total intangible liability carrying amount	38,300	38,300
Net intangible assets carrying amount	221,398	221,398
Accumulated amortization	(129,815)	(115,167)
Net intangible assets subject to amortization	91,583	106,231
Net intangible assets subject to amortization	118,195	138,103
LTSA
Finite-Lived Intangible Assets [Line Items]
Total intangible liability carrying amount	24,100	24,100
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Total intangible liability carrying amount	14,200	14,200
Cleco Katrina/Rita right to bill and collect storm recovery charges
Finite-Lived Intangible Assets [Line Items]
Total intangible assets carrying amount	70,594	70,594
Cleco Katrina/Rita right to bill and collect storm recovery charges | CLECO POWER
Finite-Lived Intangible Assets [Line Items]
Total intangible assets carrying amount	177,537	177,537
Accumulated amortization	(177,537)	(177,020)
Net intangible assets subject to amortization	0	517
Trade name
Finite-Lived Intangible Assets [Line Items]
Total intangible assets carrying amount	5,100	5,100
Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Total intangible assets carrying amount	$ 184,004	$ 184,004