Pension Plan and Employee Benefits, SERP (Details) - SERP Benefits [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 30, 2017	Mar. 29, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate (in hundredths)			4.08%	4.22%
Components of periodic benefit costs [Abstract]
Current portion of SERP liability	$ 4,308				$ 4,308
Noncurrent portion of SERP liability	77,329				73,738
Cleco Power [Member]
Components of periodic benefit costs [Abstract]
Total benefit cost	300	$ 400
Current portion of SERP liability	885				885
Noncurrent portion of SERP liability	16,075				$ 15,145
Successor [Member]
Components of periodic benefit costs [Abstract]
Service cost	145
Interest cost	800
Prior period service (credit) cost	(57)
Net loss (gain)	419
Net periodic benefit cost	1,307
Special/contractual termination benefits	315
Total benefit cost	$ 1,622
Predecessor [Member]
Components of periodic benefit costs [Abstract]
Service cost		583
Interest cost		731
Prior period service (credit) cost		13
Net loss (gain)		655
Net periodic benefit cost		1,982
Special/contractual termination benefits		0
Total benefit cost		$ 1,982