Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Litigation (Details)			1 Months Ended					12 Months Ended	24 Months Ended
	May 22, 2018 USD ($)	Mar. 07, 2018 plaintiff	Jun. 30, 2016 petition	Sep. 30, 2015 USD ($)	Jun. 30, 2015 claim	Feb. 28, 2015	Nov. 30, 2014	Dec. 31, 2016 claim	Dec. 31, 2017 USD ($)	Mar. 31, 2019 USD ($)	Feb. 04, 2019 USD ($)	Dec. 31, 2018 USD ($)	Aug. 31, 2018 USD ($)	Mar. 31, 2017 generation_unit
Loss Contingencies [Line Items]
Provision for rate refund										$ 44,002,000		$ 35,842,000
Indemnification asset											$ 10,000,000
Loss contingency, estimate of possible loss										4,600,000
FERC | MISO Transmission Rates
Loss Contingencies [Line Items]
Public utilities, requested rate increase (decrease), percentage (in hundredths)							0.50%
Gulf Coast Spinning start up costs
Loss Contingencies [Line Items]
Allegations by plaintiff, failure to perform				$ 6,500,000
Gulf Coast Spinning construction of cotton spinning facility
Loss Contingencies [Line Items]
Allegations by plaintiff, failure to perform				$ 60,000,000
Actions filed in the 9th Judicial District Court | Alleged Breach of Fiduciary Duties
Loss Contingencies [Line Items]
Number of actions filed | claim								4
Actions filed in the Civil District Court | Alleged Breach of Fiduciary Duties
Loss Contingencies [Line Items]
Number of actions filed | claim					3			3
Perry Bonin, Ace Chandler, and Michael Manuel, et al v. Sabine River Authority of Texas and Sabine River Authority of Louisiana, No. B-160173-C | Pending Litigation
Loss Contingencies [Line Items]
Number of generation units failed to repair | generation_unit														1
Number of generation units owned | generation_unit														2
Larry Addison, Et Al. V. Sabine River Authority Of Texas, Et Al | Pending Litigation
Loss Contingencies [Line Items]
Number of plaintiffs | plaintiff		26
CLECO POWER
Loss Contingencies [Line Items]
Provision for rate refund										44,002,000		$ 35,842,000
CLECO POWER | LPSC 2016-2017 Fuel Audit
Loss Contingencies [Line Items]
Fuel costs									$ 536,200,000
Cost disallowance in audit, excluding interest													$ 0
CLECO POWER | LPSC 2016-2017 EAC Audit
Loss Contingencies [Line Items]
Loss contingency, damages sought, value	$ 30,700,000
CLECO POWER | LPSC Nov 2010-Dec 2015 EAC Audit
Loss Contingencies [Line Items]
Number of petitions filed with the U.S. Court of Appeals | petition			6
CLECO POWER | FERC | MISO Transmission Rates
Loss Contingencies [Line Items]
Public utilities, approved return on equity, percentage (In hundredths)						12.38%
Public utilities, proposed return on equity, percentage (in hundredths)			9.70%			6.68%
Provision for rate refund										$ 1,900,000