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For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related costs.

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Percentage of public utility's approved return on equity.

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Regulation and Rates (Details)			1 Months Ended			12 Months Ended
Regulation and Rates (Details)	Apr. 13, 2016 USD ($)	Apr. 07, 2016 USD ($)	Sep. 30, 2016	Jun. 30, 2014	Nov. 30, 2013 claim	Dec. 31, 2018 USD ($) claim agreement	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Oct. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Feb. 28, 2017 USD ($)
Public Utilities, General Disclosures [Line Items]
Provision for rate refund						$ 35,842,000	$ 4,206,000
Rate credits \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	$ 136,000,000
Contributions for economic development \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	2,500,000
Economic development contribution \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	7,000,000
Charitable contributions to be disbursed over five years \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	6,000,000
Cost savings \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	1,200,000
CLECO POWER
Public Utilities, General Disclosures [Line Items]
Estimated refund for the tax-related benefits from the TCJA						31,600,000
Provision for rate refund						35,842,000	4,206,000
Payments received for capital expenditures subject to refund						1,800,000
Other operations						(82,330,000)	(77,522,000)	$ (68,573,000)
Power purchased for utility customers						(168,180,000)	$ (152,913,000)	$ (119,586,000)
CLECO POWER \| FERC
Public Utilities, General Disclosures [Line Items]
Other operations						1,600,000
Power purchased for utility customers						$ 900,000
CLECO POWER \| FERC \| MISO Transmission Rates
Public Utilities, General Disclosures [Line Items]
Number of claims filed \| claim					2	2
Provision for rate refund											$ 1,200,000
Return on equity established by FERC			10.32%		12.38%
CLECO POWER \| FERC \| Transmission return on equity
Public Utilities, General Disclosures [Line Items]
Provision for rate refund						$ 1,900,000
CLECO POWER \| FERC \| SSR
Public Utilities, General Disclosures [Line Items]
Amount to be collected annually from a regional transmission organization						20,300,000
CLECO POWER \| FERC \| SSR 2
Public Utilities, General Disclosures [Line Items]
Amount to be collected annually from a regional transmission organization						$ 11,800,000
Number of agreements settled \| agreement						2
CLECO POWER \| LPSC \| FRP
Public Utilities, General Disclosures [Line Items]
Return on equity established by FERC				10.00%
Percentage of retail earnings within range to be returned to customers				60.00%
Return on equity for customer credit, low range				10.90%
Return on equity for customer refund, high range				11.75%
CLECO POWER \| LPSC \| 2017 FRP Monitoring report
Public Utilities, General Disclosures [Line Items]
Provision for rate refund										$ 0
CLECO POWER \| LPSC \| 2017 Merger Commitment Monitoring report
Public Utilities, General Disclosures [Line Items]
Provision for rate refund										$ 1,200,000
CLECO POWER \| LPSC \| 2016 FRP Monitoring report
Public Utilities, General Disclosures [Line Items]
Provision for rate refund		$ 1,200,000
CLECO POWER \| LPSC \| 2018 FRP Monitoring report
Public Utilities, General Disclosures [Line Items]
Provision for rate refund									$ 0
CLECO POWER \| LPSC \| 2018 Merger Commitment Monitoring report
Public Utilities, General Disclosures [Line Items]
Provision for rate refund									$ 1,200,000
CLECO POWER \| MAXIMUM \| LPSC \| FRP
Public Utilities, General Disclosures [Line Items]
Return on equity established by FERC				10.90%
CLECO POWER \| Rate credits \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	136,000,000	136,000,000
Rate credits issued to customers						$ 135,100,000
CLECO POWER \| Contributions for economic development \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	$ 2,500,000	$ 2,500,000
Disbursement period	5 years	5 years
CLECO POWER \| Economic development contribution \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	$ 7,000,000	$ 7,000,000
CLECO POWER \| Charitable contributions to be disbursed over five years \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	$ 6,000,000	$ 6,000,000
Disbursement period	5 years	5 years
CLECO POWER \| Cost savings \| LPSC
Public Utilities, General Disclosures [Line Items]
Merger commitments	$ 1,200,000	$ 1,200,000
Refunds submitted to MISO						$ 5,900,000