Storm Restoration (Details) customer in Thousands, $ in Thousands		1 Months Ended		2 Months Ended	9 Months Ended
	May 19, 2021 USD ($)	May 31, 2021	Mar. 31, 2021 USD ($)	Oct. 28, 2020 USD ($) hurricane	Sep. 30, 2021 USD ($)	Sep. 28, 2021 USD ($)	Sep. 11, 2021	Aug. 29, 2021 customer	Aug. 05, 2021 USD ($)	Mar. 29, 2021 USD ($)	Feb. 17, 2021 customer	Feb. 14, 2021 customer	Dec. 31, 2020 USD ($)
Unusual or Infrequent Item, or Both [Line Items]
Securitized storm restoration costs									$ 342,000
Securitized storm restoration costs, reserve for future costs									$ 100,000
Hurricanes
Unusual or Infrequent Item, or Both [Line Items]
Capitalization percentage				63.00%
Capitalized storm restoration costs, interim storm recovery amount	$ 16,000
Deferred storm restoration costs - Winter Storms Uri & Viola
Unusual or Infrequent Item, or Both [Line Items]
Capitalization percentage					80.00%
Deferred storm restoration costs - Hurricane Ida
Unusual or Infrequent Item, or Both [Line Items]
Securitized storm restoration costs, reserve for future costs						$ 100,000
CLECO POWER
Unusual or Infrequent Item, or Both [Line Items]
Regulatory assets					$ 721,426								$ 456,034
CLECO POWER | Hurricane Laura, Delta and Zeta
Unusual or Infrequent Item, or Both [Line Items]
Regulatory assets					78,200
CLECO POWER | Deferred storm restoration costs - Winter Storms Uri & Viola
Unusual or Infrequent Item, or Both [Line Items]
Regulatory assets					1,974								0
CLECO POWER | Deferred storm restoration costs - Hurricane Ida
Unusual or Infrequent Item, or Both [Line Items]
Regulatory assets					36,836								$ 0
CLECO POWER | Hurricanes
Unusual or Infrequent Item, or Both [Line Items]
Number of hurricanes | hurricane				3
Estimate of storm restoration costs				$ 242,600
Capitalized storm restoration costs				$ 152,200
CLECO POWER | Deferred storm restoration costs - Winter Storms Uri & Viola
Unusual or Infrequent Item, or Both [Line Items]
Estimate of storm restoration costs					10,500
Capitalized storm restoration costs					8,400					$ 50,000
Capitalized storm restoration costs, amortization period		12 months
Fuel and purchased power costs					$ 55,000
CLECO POWER | Deferred storm restoration costs - Winter Storms Uri & Viola | Letters of Credit
Unusual or Infrequent Item, or Both [Line Items]
Collateral returned			$ 24,900
CLECO POWER | Winter Storm Uri
Unusual or Infrequent Item, or Both [Line Items]
Number of customers affected with power outage | customer												11
CLECO POWER | Winter Storm Viola
Unusual or Infrequent Item, or Both [Line Items]
Number of customers affected with power outage | customer											43
CLECO POWER | Deferred storm restoration costs - Hurricane Ida
Unusual or Infrequent Item, or Both [Line Items]
Capitalization percentage					56.00%
Capitalized storm restoration costs					$ 49,100
Number of customers affected with power outage | customer								100
Percentage of customers affected by the hurricane with power restored							100.00%
CLECO POWER | Deferred storm restoration costs - Hurricane Ida | Minimum
Unusual or Infrequent Item, or Both [Line Items]
Estimate of storm restoration costs					85,000
CLECO POWER | Deferred storm restoration costs - Hurricane Ida | Maximum
Unusual or Infrequent Item, or Both [Line Items]
Estimate of storm restoration costs					$ 95,000
Cleco Cajun | Deferred storm restoration costs - Winter Storms Uri & Viola | Letters of Credit
Unusual or Infrequent Item, or Both [Line Items]
Collateral returned			$ 6,500