Pension Plan and Employee Benefits - Amounts Recognized in Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Non-current	$ 249,264	$ 242,135
OTHER BENEFITS
Defined Benefit Plan Disclosure [Line Items]
Current	4,130	4,061
Non-current	36,325	39,142
SERP BENEFITS
Defined Benefit Plan Disclosure [Line Items]
SERP, current	4,478	4,471
SERP, noncurrent	73,936	79,868
CLECO POWER
Defined Benefit Plan Disclosure [Line Items]
Non-current	182,721	173,747
CLECO POWER | OTHER BENEFITS
Defined Benefit Plan Disclosure [Line Items]
Current	3,584	3,525
Non-current	31,694	34,033
CLECO POWER | SERP BENEFITS
Defined Benefit Plan Disclosure [Line Items]
SERP, current	930	929
SERP, noncurrent	$ 12,025	$ 16,589