The aggregate expected value at the end of their useful life of a major finite-lived intangible asset class acquired during the period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Intangible Assets and Goodwill (Details) - USD ($)	3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended
Intangible Assets and Goodwill (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2008	Apr. 13, 2016
Finite-Lived Intangible Assets [Line Items]
Goodwill							$ 1,491,519,000
Cleco Katrina/Rita right to bill and collect storm recovery charges from customers [Member] \| Other Subsidiaries [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired						$ 177,500,000
Acquired Finite-lived Intangible Asset, Residual Value						$ 0
Accumulated Amortization as of the Date of the Merger							$ 0
Amortization	$ 4,900,000	$ 4,400,000		$ 13,100,000	$ 12,000,000
Cleco Katrina/Rita right to bill and collect storm recovery charges from customers [Member] \| Minimum [Member] \| Other Subsidiaries [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life						12 years
Cleco Katrina/Rita right to bill and collect storm recovery charges from customers [Member] \| Maximum [Member] \| Other Subsidiaries [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life						15 years
Contractual Rights [Member] \| Other Subsidiaries [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired						$ 176,000,000
Financing costs [Member] \| Other Subsidiaries [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired						$ 1,500,000
Cleco Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Residual Value	0		$ 0	$ 0
Intangible Asset, Useful Life				20 years
Wholesale power supply agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Residual Value	0		0	$ 0
Wholesale power supply agreements [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Asset, Useful Life				2 years
Wholesale power supply agreements [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible Asset, Useful Life				19 years
Successor [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	1,491,519,000		1,491,519,000	$ 1,491,519,000
Successor [Member] \| Cleco Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization	100,000		100,000
Successor [Member] \| Wholesale power supply agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization	$ 2,600,000		$ 4,800,000