Summary of Significant Accounting Policies, Restricted Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Restricted Cash and Cash Equivalents Items [Line Items]
Current	$ 6,727	$ 13,081
Non-current	19,327	20,081
Total restricted cash and cash equivalents	26,054	33,162
Cleco Katrina/Rita’s storm recovery bonds
Restricted Cash and Cash Equivalents Items [Line Items]
Current	2,601	8,597
Charitable contributions
Restricted Cash and Cash Equivalents Items [Line Items]
Current	1,200	1,200
Non-current	3,044	3,575
Rate credit escrow
Restricted Cash and Cash Equivalents Items [Line Items]
Current	2,926	3,284
Non-current	1,557	2,029
Diversified Lands’ mitigation escrow
Restricted Cash and Cash Equivalents Items [Line Items]
Non-current	21	21
Future storm restoration costs
Restricted Cash and Cash Equivalents Items [Line Items]
Non-current	14,705	14,456
Cleco Katrina/Rita Bond Principal Payments
Restricted Cash and Cash Equivalents Items [Line Items]
Increase (decrease) in restricted cash	(9,700)
Cleco Katrina/Rita Bond Interest Payments [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Increase (decrease) in restricted cash	(1,400)
Cleco Katrina/Rita storm recovery collections, net of administration fees
Restricted Cash and Cash Equivalents Items [Line Items]
Increase (decrease) in restricted cash	5,100
Cleco Power
Restricted Cash and Cash Equivalents Items [Line Items]
Current	6,727	13,081
Non-current	19,306	20,060
Total restricted cash and cash equivalents	26,033	33,141
Cleco Power \| Cleco Katrina/Rita’s storm recovery bonds
Restricted Cash and Cash Equivalents Items [Line Items]
Current	2,601	8,597
Cleco Power \| Charitable contributions
Restricted Cash and Cash Equivalents Items [Line Items]
Current	1,200	1,200
Non-current	3,044	3,575
Cleco Power \| Rate credit escrow
Restricted Cash and Cash Equivalents Items [Line Items]
Current	2,926	3,284
Non-current	1,557	$ 2,029
Cleco Power \| Future storm restoration costs
Restricted Cash and Cash Equivalents Items [Line Items]
Non-current	$ 14,705

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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