Summary of Significant Accounting Policies, Restricted Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	9 Months Ended		18 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Dec. 31, 2016	Apr. 01, 2016
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	$ 8,874		$ 8,874	$ 23,084
Total non-current	24,547		24,547	23,410
Total restricted cash and cash equivalents	33,421		33,421	46,494
Cleco Katrina Rita Storm Recovery Bonds
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	3,798		3,798	9,213
Cleco Power's charitable contributions [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	1,200		1,200	1,200
Total non-current	3,640		3,640	4,179
Cleco Power's rate credit escrow [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	3,876		3,876	12,671
Total non-current	2,887		2,887	1,831
Diversified Lands’ mitigation escrow
Restricted Cash and Cash Equivalents Items [Line Items]
Total non-current	21		21	21
Cleco Power’s future storm restoration costs
Restricted Cash and Cash Equivalents Items [Line Items]
Total non-current	17,999		17,999	17,379
Katrina Rita storm recovery collections, net of administration fees
Restricted Cash and Cash Equivalents Items [Line Items]
Increase (Decrease) in Restricted Cash	16,100
Katrina Rita Bond Principal Payments
Restricted Cash and Cash Equivalents Items [Line Items]
Increase (Decrease) in Restricted Cash	(17,900)
Katrina Rita Bond Interest Payments [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Increase (Decrease) in Restricted Cash	(3,600)
Cleco Power [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	8,874		8,874	23,084
Total non-current	24,526		24,526	23,389
Total restricted cash and cash equivalents	33,400		33,400	46,473
Increase (Decrease) in Restricted Cash	(13,073)	$ 29,096
Cleco Power [Member] | Cleco Katrina Rita Storm Recovery Bonds
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	3,798		3,798	9,213
Cleco Power [Member] | Cleco Power's charitable contributions [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	1,200		1,200	1,200
Total non-current	3,640		3,640	4,179
Total restricted cash and cash equivalents					$ 6,000
Increase (Decrease) in Restricted Cash			(1,200)
Cleco Power [Member] | Cleco Power's rate credit escrow [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total current	3,876		3,876	12,671
Total non-current	2,887		2,887	1,831
Total restricted cash and cash equivalents					$ 136,000
Increase (Decrease) in Restricted Cash			(129,400)
Cleco Power [Member] | Cleco Power’s future storm restoration costs
Restricted Cash and Cash Equivalents Items [Line Items]
Total non-current	$ 17,999		$ 17,999	$ 17,379