Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees - Off-Balance Sheet Commitments and Guarantees (Details)	3 Months Ended
	Mar. 31, 2020 USD ($)
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 | Indemnification Agreement
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	40,000,000
CLECO POWER | Indemnification Agreement including fundamental organizational structure
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	400,000,000
CLECO POWER | Financial Guarantee
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	83,000,000.0
CLECO HOLDINGS | Letters of Credit
Guarantor Obligations [Line Items]
Letters of credit	$ 34,500,000