Intangible Assets and Goodwill - Schedule of Amortization of Intangible Assets (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 12, 2016	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CLECO POWER | Cleco Katrina/Rita right to bill and collect storm recovery charges
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets			$ 20,608,000	$ 16,772,000	$ 16,490,000
SUCCESSOR
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ 19,786,000	30,543,000	27,784,000
Impairments for intangibles		0	0	0
SUCCESSOR | Trade name
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		183,000	255,000	255,000
SUCCESSOR | Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		7,482,000	9,680,000	10,757,000
SUCCESSOR | Cleco Katrina/Rita | Cleco Katrina/Rita right to bill and collect storm recovery charges
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ 12,121,000	$ 20,608,000	$ 16,772,000
PREDECESSOR
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 4,369,000
Impairments for intangibles	0
PREDECESSOR | Trade name
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	0
PREDECESSOR | Power supply agreements
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	0
PREDECESSOR | Cleco Katrina/Rita | Cleco Katrina/Rita right to bill and collect storm recovery charges
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 4,369,000