Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Off-Balance Sheet Commitments and Guarantees (Details) - USD ($)	1 Months Ended	6 Months Ended
	Mar. 31, 2021	Jun. 30, 2021
Guarantor Obligations [Line Items]
Guarantor obligations, collateral held directly or by third parties, amount		$ 0
Performance Guarantee
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted		42,400,000
Indemnification Agreement
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted		40,000,000.0
Indemnification Agreement including fundamental organizational structure
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted		400,000,000.0
CLECO POWER
Guarantor Obligations [Line Items]
Guarantor obligations, collateral held directly or by third parties, amount		0
CLECO POWER | Letters of Credit | Deferred storm restoration costs - Winter Storms Uri & Viola
Guarantor Obligations [Line Items]
Collateral returned	$ 24,900,000
CLECO POWER | Indemnification Agreement
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted		40,000,000.0
CLECO POWER | Indemnification Agreement including fundamental organizational structure
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted		400,000,000.0
CLECO POWER | Financial Guarantee
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted		$ 25,000,000.0
Cleco Cajun | Letters of Credit | Deferred storm restoration costs - Winter Storms Uri & Viola
Guarantor Obligations [Line Items]
Collateral returned	$ 6,500,000