Summary of Significant Accounting Policies, AFUDC (Details) - Cleco Power [Member]	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Public Utilities, General Disclosures [Line Items]
Composite AFUDC rate, including borrowed and other funds, net of tax	6.81%	7.39%	7.09%
Composite AFUDC rate, including borrowed and other funds, pre-tax	11.07%	11.94%	11.46%

Effective rate, including composite rate, of cost of financing additions to qualifying regulated assets, commonly called allowance for funds used during construction.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 835
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501662&loc=d3e56162-110433

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 835
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501569&loc=d3e55921-110430

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