Pension Plan and Employee Benefits, Pension Plan and Other Benefits Plan (Details) - USD ($)		3 Months Ended				6 Months Ended
	Apr. 12, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2016	Apr. 12, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Other Benefits [Member]
Components of periodic benefit costs [Abstract]
Assets Held-in-trust, Noncurrent		$ 0				$ 0
Current portion of other benefits liability		3,854,000				3,854,000		$ 3,854,000
Noncurrent portion of other benefits liability		39,631,000				39,631,000		40,196,000
Other Benefits [Member] | Cleco Power
Components of periodic benefit costs [Abstract]
Net periodic benefit cost		900,000	$ 800,000			1,700,000	$ 1,700,000
Current portion of other benefits liability		3,345,000				3,345,000		3,345,000
Noncurrent portion of other benefits liability		34,407,000				34,407,000		$ 34,892,000
Successor | Pension Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost		2,295,000		$ 1,893,000		4,520,000
Interest cost		5,467,000		4,669,000		10,824,000
Expected return on plan assets		(5,895,000)		(5,193,000)		12,032,000
Prior period service (credit) cost		(18,000)		(15,000)		(36,000)
Net loss (gain)		2,591,000		1,845,000		(5,004,000)
Net periodic benefit cost		4,440,000		3,199,000		8,280,000
Successor | Pension Benefits [Member] | Other Subsidiaries [Member]
Components of periodic benefit costs [Abstract]
Net periodic benefit cost		500,000	$ 900,000	400,000
Successor | Other Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost		385,000		329,000		770,000
Interest cost		402,000		364,000		805,000
Expected return on plan assets		0		0		0
Prior period service (credit) cost		0		0		0
Net loss (gain)		(2,000)		0		5,000
Net periodic benefit cost		$ 785,000		$ 693,000		$ 1,570,000
Predecessor | Pension Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost	$ 301,000				$ 2,563,000
Interest cost	734,000				6,242,000
Expected return on plan assets	(801,000)				(6,812,000)
Prior period service (credit) cost	(2,000)				(20,000)
Net loss (gain)	329,000				2,798,000
Net periodic benefit cost	561,000				4,771,000
Predecessor | Pension Benefits [Member] | Other Subsidiaries [Member]
Components of periodic benefit costs [Abstract]
Net periodic benefit cost	100,000				500,000
Predecessor | Other Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost	51,000				431,000
Interest cost	56,000				476,000
Expected return on plan assets	0				0
Prior period service (credit) cost	4,000				34,000
Net loss (gain)	21,000				181,000
Net periodic benefit cost	$ 132,000				$ 1,122,000