The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Summary of Significant Accounting Policies, Restricted Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Sep. 30, 2017	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Apr. 30, 2016
Restricted Cash and Cash Equivalents [Abstract]
Current			$ 13,081	$ 23,084
Non-current			20,081	23,410
Total restricted cash and cash equivalents			33,162	46,494
Cleco Katrina Rita Storm Recovery Bonds [Member]
Restricted Cash and Cash Equivalents [Abstract]
Current			8,597	9,213
Cleco Power's Charitable Contributions [Member]
Restricted Cash and Cash Equivalents [Abstract]
Current			1,200	1,200
Non-current			3,575	4,179
Cleco Power's Rate Credit Escrow [Member]
Restricted Cash and Cash Equivalents [Abstract]
Current			3,284	12,671
Non-current			2,029	1,831
Diversified Lands Mitigation Escrow [Member]
Restricted Cash and Cash Equivalents [Abstract]
Non-current			21	21
Cleco Power's Future Storm Restoration Costs [Member]
Restricted Cash and Cash Equivalents [Abstract]
Non-current			14,456	17,379
Katrina/Rita Storm Recovery Collections, Net of Administration Fees [Member]
Restricted Cash and Cash Equivalents [Abstract]
Increase (Decrease) in Restricted Cash			20,900
Katrina Rita Bond Principal Payments [Member]
Restricted Cash and Cash Equivalents [Abstract]
Increase (Decrease) in Restricted Cash	$ 8,800	$ 9,100
Katrina Rita Bond Interest Payments [Member]
Restricted Cash and Cash Equivalents [Abstract]
Increase (Decrease) in Restricted Cash	$ 1,700	$ 1,900
Cleco Power [Member]
Restricted Cash and Cash Equivalents [Abstract]
Current			13,081	23,084
Non-current			20,060	23,389
Total restricted cash and cash equivalents			33,141	46,473
Increase (Decrease) in Restricted Cash			(13,332)	21,037	$ 1,341
Cleco Power [Member] \| Cleco Katrina Rita Storm Recovery Bonds [Member]
Restricted Cash and Cash Equivalents [Abstract]
Current			8,597	9,213
Cleco Power [Member] \| Cleco Power's Charitable Contributions [Member]
Restricted Cash and Cash Equivalents [Abstract]
Current			1,200	1,200
Non-current			3,575	4,179
Total restricted cash and cash equivalents						$ 6,000
Increase (Decrease) in Restricted Cash			(1,300)
Cleco Power [Member] \| Cleco Power's Rate Credit Escrow [Member]
Restricted Cash and Cash Equivalents [Abstract]
Current			3,284	12,671
Non-current			2,029	1,831
Total restricted cash and cash equivalents						$ 136,000
Increase (Decrease) in Restricted Cash			(130,800)
Cleco Power [Member] \| Cleco Power's Future Storm Restoration Costs [Member]
Restricted Cash and Cash Equivalents [Abstract]
Non-current			$ 14,456	$ 17,379