Summary of Significant Accounting Policies - Reclassifications (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Depreciation and amortization		$ 400	$ 7,300
Other operations and maintenance		400	7,300
CLECO POWER
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Depreciation and amortization	$ (162,069)	(158,415)	(153,393)
Other operations and maintenance	$ 202,556	202,738	203,452
CLECO POWER | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Depreciation and amortization		400	7,300
Other operations and maintenance		$ 400	$ 7,300