Fair Value Accounting and Financial Instruments - Institutional Money Market Funds (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Cash equivalents	$ 145,011	$ 80,712
Cleco Power
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Cash equivalents	82,411	20,812
Restricted Cash and Cash Equivalents, Current
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Restricted cash and cash equivalents	0	4,545
Restricted Cash and Cash Equivalents, Current | Cleco Power
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Restricted cash and cash equivalents	0	4,545
Restricted Cash and Cash Equivalents, Noncurrent
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Restricted cash and cash equivalents	$ 22	$ 744