Affiliate Transactions - Summary of Balances Payable To or Due From Affiliates (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
ACCOUNTS RECEIVABLE	$ 2,686	$ 1,663
ACCOUNTS PAYABLE	41,283	41,283
CLECO POWER
Related Party Transaction [Line Items]
ACCOUNTS RECEIVABLE	13,026	14,605
ACCOUNTS PAYABLE	70,437	72,068
CLECO POWER | Cleco Holdings
Related Party Transaction [Line Items]
ACCOUNTS RECEIVABLE	10,383	10,353
ACCOUNTS PAYABLE	57,696	57,713
CLECO POWER | Support Group
Related Party Transaction [Line Items]
ACCOUNTS RECEIVABLE	1,707	3,248
ACCOUNTS PAYABLE	12,737	14,355
CLECO POWER | Cleco Cajun
Related Party Transaction [Line Items]
ACCOUNTS RECEIVABLE	936	1,004
ACCOUNTS PAYABLE	$ 4	$ 0