Affiliate Transactions - Summary of Balances Payable To or Due From Affiliates (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Affiliate Transaction [Line Items]
Accounts payable - affiliate	$ 41,283	$ 33,780
Cleco Power
Affiliate Transaction [Line Items]
Accounts receivable - affiliate	14,605	14,481
Accounts payable - affiliate	72,068	14,123
Cleco Holdings
Affiliate Transaction [Line Items]
Accounts payable - affiliate	41,300	33,800
Cleco Holdings \| Cleco Power
Affiliate Transaction [Line Items]
Accounts receivable - affiliate	10,353	10,351
Accounts payable - affiliate	57,713	194
Support Group \| Cleco Power
Affiliate Transaction [Line Items]
Accounts receivable - affiliate	3,248	3,172
Accounts payable - affiliate	14,355	13,890
Cleco Cajun \| Cleco Power
Affiliate Transaction [Line Items]
Accounts receivable - affiliate	1,004	958
Accounts payable - affiliate	$ 0	$ 39

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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Name:	us-gaap_DueFromRelatedPartiesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant