Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees, Off-Balance Sheet Commitments (Details) - USD ($) $ in Millions	Jun. 30, 2015	Mar. 15, 2014	Jan. 31, 2006
Performance Guarantee [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 42.4
Cleco Power [Member] | Guarantee Issued to Entergy Mississippi on behalf of Attala [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	69.3
Attala [Member] | Cleco Corporation [Member] | Guarantee Issued to Entergy Mississippi on behalf of Attala [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted			$ 0.5
Louisiana Department of Labor [Member] | Cleco Power [Member] | Obligations Under Standby Letter of Credit [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 3.7
Percentage of average losses on which letter of credit is based (in hundredths)	110.00%
MISO [Member] | Cleco Power [Member] | Obligations Under Standby Letter of Credit [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 2.0
Evangeline [Member] | Transfer of assets from affiliate [Member] | Indemnification Agreement [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 40.0
Evangeline [Member] | Transfer of assets from affiliate [Member] | Indemnification Agreement INCLUDING fundamental organizational structure [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted		400.0
Evangeline [Member] | Transfer of assets from affiliate [Member] | Cleco Power [Member] | Indemnification Agreement [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted		40.0
Evangeline [Member] | Transfer of assets from affiliate [Member] | Cleco Power [Member] | Indemnification Agreement INCLUDING fundamental organizational structure [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 400.0