Fair Value Accounting, Carrying Value and Estimated Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Financial instruments not marked-to-market [Abstract]
Deferred debt issuance costs not included in the carrying value of long-term debt	$ 11,700	$ 11,700
Estimated Fair Value [Member]
Financial instruments not marked-to-market [Abstract]
Long-term debt	2,766,056	2,754,518
Carrying Value [Member]
Financial instruments not marked-to-market [Abstract]
Long-term debt	2,756,889	2,768,149
Cleco Power [Member]
Financial instruments not marked-to-market [Abstract]
Deferred debt issuance costs not included in the carrying value of long-term debt	8,800	9,400
Cleco Power [Member] | Estimated Fair Value [Member]
Financial instruments not marked-to-market [Abstract]
Long-term debt	1,418,027	1,418,693
Cleco Power [Member] | Carrying Value [Member]
Financial instruments not marked-to-market [Abstract]
Long-term debt	$ 1,253,410	$ 1,262,373