Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees, Litigation (Details) $ in Thousands	1 Months Ended				3 Months Ended	60 Months Ended
	Nov. 30, 2014	Nov. 30, 2013	Jul. 31, 2010 USD ($) plaintiff	Dec. 31, 2009 USD ($)	Sep. 30, 2015 USD ($) plaintiff	Dec. 31, 2013 USD ($)	Dec. 31, 2014 USD ($)
Litigation [Abstract]
Provision for rate refund					$ 4,164		$ 2,264
Other Litigation Matters [Member]
Litigation [Abstract]
Amount of estimated possible loss					5,300
Cleco Power [Member]
Litigation [Abstract]
Provision for rate refund					$ 4,164		$ 2,264
Pending Litigation [Member] | Petition for breach of fiduciary duties in proposed merger [Member]
Litigation [Abstract]
Loss contingency, number of plaintiffs (in ones) | plaintiff					7
Dismissed litigation [Member] | Discrimination Complaint [Member]
Litigation [Abstract]
Loss contingency, number of plaintiffs (in ones) | plaintiff			13
Dismissed litigation [Member] | Minimum [Member] | Discrimination Complaint [Member]
Litigation [Abstract]
Loss contingency, damages sought, minimum amount			$ 2,500	$ 35,000
LPSC 2009-2013 audit of fuel [Member] | Cleco Power [Member]
Litigation [Abstract]
Fuel expenses included in the audit						$ 1,730,000
FERC [Member] | MISO Transmission Rates [Member]
Litigation [Abstract]
Current Return on Equity, Percentage (in hundredths)		12.38%
Proposed Return on Equity, Percentage (in hundredths)		6.68%
Requested increase to Return on Equity, Percentage (in hundredths)	0.50%
FERC [Member] | Transmission ROE [Member] | Cleco Power [Member]
Litigation [Abstract]
Provision for rate refund					$ 2,800