Affiliate Transactions - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Accounts receivable - affiliate	$ 2,686		$ 2,686		$ 1,663
Accounts payable - affiliate	41,283		41,283		41,283
CLECO POWER
Related Party Transaction [Line Items]
Accounts receivable - affiliate	13,026		13,026		14,605
Accounts payable - affiliate	70,437		70,437		72,068
CLECO POWER | Cleco Holdings
Related Party Transaction [Line Items]
Accounts receivable - affiliate	10,383		10,383		10,353
Accounts payable - affiliate	57,696		57,696		57,713
CLECO POWER | Cleco Holdings | Settlement of taxes payable
Related Party Transaction [Line Items]
Accounts payable - affiliate	57,600		57,600		57,600
CLECO POWER | Affiliates
Related Party Transaction [Line Items]
Accounts receivable - affiliate	1,707		1,707		3,248
Accounts payable - affiliate	12,737		12,737		14,355
CLECO POWER | Oxbow | Affiliates
Related Party Transaction [Line Items]
Cost of mineral rights and land leases	900	$ 14,600	1,900	$ 15,500
Due to affiliates	$ 300		$ 300		$ 300