Regulation and Rates - Provision for Rate Refund (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jul. 31, 2019
Regulation and Rates [Line Items]
Provision for rate refund	$ 20,428	$ 38,903
TCJA tax-related benefits
Regulation and Rates [Line Items]
Provision for rate refund	10,000	28,700
FERC audit
Regulation and Rates [Line Items]
Provision for rate refund	3,700	3,500
Cost of service savings
Regulation and Rates [Line Items]
Provision for rate refund	2,500	1,900
Cleco Katrina/Rita storm recovery charges
Regulation and Rates [Line Items]
Provision for rate refund	1,600	0
Site-specific industrial customer
Regulation and Rates [Line Items]
Provision for rate refund	1,100	800
Change in transmission ROE
Regulation and Rates [Line Items]
Provision for rate refund	800	1,000
CLECO POWER
Regulation and Rates [Line Items]
Provision for rate refund	19,614	38,241	$ 79,200
CLECO POWER | TCJA tax-related benefits
Regulation and Rates [Line Items]
Provision for rate refund	10,000	28,700
CLECO POWER | FERC audit
Regulation and Rates [Line Items]
Provision for rate refund	3,700	3,500
CLECO POWER | Cost of service savings
Regulation and Rates [Line Items]
Provision for rate refund	2,500	1,900
CLECO POWER | Cleco Katrina/Rita storm recovery charges
Regulation and Rates [Line Items]
Provision for rate refund	1,600	0
CLECO POWER | Site-specific industrial customer
Regulation and Rates [Line Items]
Provision for rate refund	1,100	800
CLECO POWER | Change in transmission ROE
Regulation and Rates [Line Items]
Provision for rate refund	$ 800	$ 1,000