Pension Plan and Employee Benefits, Pension Plan and Other Benefits Plan (Details) - USD ($)	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2016	Apr. 12, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.21%	4.62%		4.21%	4.21%
Defined Benefit Plan, Expected Annual Net Periodic Benefit Cost		$ 15,900,000		$ 17,500,000
Other Benefits [Member]
Components of periodic benefit costs [Abstract]
Assets Held-in-trust, Noncurrent	$ 0			0	$ 0
Other Benefits [Member] | Cleco Power [Member]
Components of periodic benefit costs [Abstract]
Net periodic benefit cost	800,000		$ 900,000		2,500,000	$ 2,700,000
Current portion of other benefits liability	3,140,000			3,140,000	3,140,000		$ 3,140,000
Noncurrent portion of other benefits liability	33,311,000			33,311,000	33,311,000		34,300,000
Successor [Member] | Pension Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost	2,229,000			4,122,000
Interest cost	5,455,000			10,124,000
Expected return on plan assets	(6,001,000)			(11,195,000)
Prior period service (credit) cost	(18,000)			(33,000)
Net loss	3,365,000			5,211,000
Net periodic benefit cost	5,030,000			8,229,000
Successor [Member] | Pension Benefits [Member] | Other Subsidiaries [Member]
Components of periodic benefit costs [Abstract]
Net periodic benefit cost	400,000			800,000
Successor [Member] | Other Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost	380,000			709,000
Interest cost	420,000			784,000
Expected return on plan assets	0			0
Prior period service (credit) cost	0			0
Net loss	0			0
Net periodic benefit cost	800,000			1,493,000
Current portion of other benefits liability	3,613,000			3,613,000	3,613,000
Noncurrent portion of other benefits liability	$ 38,333,000			$ 38,333,000	$ 38,333,000
Predecessor [Member] | Pension Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost		2,563,000	2,605,000			7,814,000
Interest cost		6,242,000	5,198,000			15,596,000
Expected return on plan assets		(6,812,000)	(5,846,000)			(17,536,000)
Prior period service (credit) cost		(20,000)	(17,000)			(53,000)
Net loss		2,798,000	3,457,000			10,371,000
Net periodic benefit cost		4,771,000	5,397,000			16,192,000
Predecessor [Member] | Pension Benefits [Member] | Other Subsidiaries [Member]
Components of periodic benefit costs [Abstract]
Net periodic benefit cost		500,000	500,000			1,500,000
Predecessor [Member] | Other Benefits [Member]
Components of periodic benefit costs [Abstract]
Service cost		431,000	442,000			1,226,000
Interest cost		476,000	461,000			1,205,000
Expected return on plan assets		0	0			0
Prior period service (credit) cost		34,000	21,000			89,000
Net loss		181,000	174,000			650,000
Net periodic benefit cost		$ 1,122,000	$ 1,098,000			$ 3,170,000
Current portion of other benefits liability							3,613,000
Noncurrent portion of other benefits liability							$ 39,457,000