Variable Interest Entities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Variable Interest Entity [Line Items]
Equity investment in investee	$ 18,172		$ 18,172		$ 18,172
Components of Equity Method Investments [Abstract]
Total equity investment in investee	18,172		18,172		18,172
CLECO POWER
Variable Interest Entity [Line Items]
Equity investment in investee	18,172		18,172		18,172
Components of Equity Method Investments [Abstract]
Purchase price	12,873		12,873		12,873
Cash contributions	6,399		6,399		6,399
Dividends	(1,100)		(1,100)		(1,100)
Total equity investment in investee	18,172		18,172		18,172
Comparison of Carrying Amount of Assets and Liabilities to Maximum Loss Exposure [Abstract]
Oxbow’s net assets/liabilities	36,345		36,345		36,345
Equity Method Investment, Summarized Financial Information [Abstract]
Operating revenue	1,057	$ 532	1,920	$ 1,605
Operating expenses	1,057	532	1,920	1,605
Income before taxes	0	$ 0	$ 0	$ 0
CLECO POWER | Oxbow
Variable Interest Entity [Line Items]
Ownership percentage by Cleco Power (in hundredths)			50.00%
Ownership percentage by other parties (in hundredths)			50.00%
Comparison of Carrying Amount of Assets and Liabilities to Maximum Loss Exposure [Abstract]
Cleco Power’s 50% equity	18,172		$ 18,172		18,172
Cleco Power’s maximum exposure to loss	$ 18,172		$ 18,172		$ 18,172