Amount to be collected annually from a regional transmission organization for system support resource payments.

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- Definition

Effective Income Tax Rate Reconciliation, At Federal And State Statutory Income Tax Rate, Percent

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Payments received for capital expenditures subject to refund

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The low range of the return on equity which triggers a retail customer partial refund obligation.

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The percentage of retail earnings to be returned to retail customers as ordered by the regulatory agency when the return on equity falls within a certain range.

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The high range of the return on equity which triggers a retail customer partial refund obligation. All retail earnings must be returned to customers when the return on equity exceeds this high range.

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- Definition

Tax Cuts And Jobs Act Of 2017, Customer Refund Liability, Current

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Current regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment.

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- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

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The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

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- Definition

Percentage of public utility's approved return on equity.

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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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No definition available.

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Amount of operating expense for purchased power of regulated operation.

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Regulation and Rates (Details)	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended	48 Months Ended
Regulation and Rates (Details)	Sep. 30, 2018 USD ($)	Sep. 30, 2016	Nov. 30, 2013	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) claim	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2018 USD ($)	Oct. 31, 2017 USD ($)	Feb. 28, 2017 USD ($)
Regulation and Rates [Line Items]
Refund due to customers	$ 26,923,000			$ 26,923,000		$ 26,923,000		$ 4,206,000
Decrease in Other operations revenue				(20,186,000)	$ (21,282,000)	(61,067,000)	$ (59,627,000)
Decrease in Power purchased for utility customers				(29,608,000)	(39,355,000)	$ (132,921,000)	(114,675,000)
Federal and state combined statutory tax rate						26.00%		38.00%
Tax Cuts and Jobs Act of 2017, customer refund liability	22,700,000			22,700,000		$ 22,700,000
CLECO POWER
Regulation and Rates [Line Items]
Refund due to customers	26,923,000			26,923,000		26,923,000		$ 4,206,000
Payments received for capital expenditures subject to refund	4,500,000			4,500,000		4,500,000
Decrease in Other operations revenue				(20,186,000)	(20,768,000)	(61,066,000)	(58,083,000)
Decrease in Power purchased for utility customers				(29,608,000)	$ (39,355,000)	$ (132,921,000)	$ (114,675,000)
CLECO POWER \| FERC
Regulation and Rates [Line Items]
Decrease in Other operations revenue	2,000,000
Decrease in Power purchased for utility customers	1,000,000
CLECO POWER \| MISO Transmission Rates \| FERC
Regulation and Rates [Line Items]
Loss contingency, new claims filed, number \| claim						2
Refund due to customers	2,100,000			2,100,000		$ 2,100,000					$ 1,200,000
Target ROE allowed by FRP		10.32%	12.38%
CLECO POWER \| FRP \| LPSC
Regulation and Rates [Line Items]
Target ROE allowed by FRP									10.00%
Percentage of retail earnings within range to be returned to customers (in hundredths)									60.00%
ROE for customer credit, low range									10.90%
ROE for customer credit, high range									11.75%
CLECO POWER \| FRP \| LPSC \| Maximum
Regulation and Rates [Line Items]
Target ROE allowed by FRP									10.90%
CLECO POWER \| 2017 FRP Monitoring Report \| LPSC
Regulation and Rates [Line Items]
Refund due to customers										$ 0
CLECO POWER \| 2017 FRP Monitoring Report, Cost of Service Savings \| LPSC
Regulation and Rates [Line Items]
Refund due to customers	1,200,000			1,200,000		1,200,000				$ 1,200,000
CLECO POWER \| 2018 FRP Monitoring Report, Earnings-Related Refunds \| LPSC
Regulation and Rates [Line Items]
Refund due to customers									$ 0
CLECO POWER \| 2018 FRP Monitoring Report, Cost of Service Savings \| LPSC
Regulation and Rates [Line Items]
Refund due to customers									$ 1,200,000
CLECO POWER \| SSR \| FERC
Regulation and Rates [Line Items]
Amount collected in SSR payments from MISO	20,300,000			20,300,000		20,300,000
CLECO POWER \| SSR 2 \| FERC
Regulation and Rates [Line Items]
Amount collected in SSR payments from MISO	$ 11,800,000			$ 11,800,000		$ 11,800,000