Pension Plan and Employee Benefits, SERP (Details) - SERP Benefits - USD ($) $ in Thousands		3 Months Ended
	Mar. 30, 2017	Mar. 31, 2018	Mar. 31, 2017
Components of periodic benefit costs
Service cost		$ 105	$ 145
Interest cost		760	800
Prior period service credit		(35)	(57)
Net loss (gain)		585	419
Net periodic benefit cost		1,415	1,307
Special/contractual termination benefits	$ 300	0	315
Net periodic benefit cost		1,415	1,622
Cleco Power
Components of periodic benefit costs
Net periodic benefit cost		$ 300	$ 300