Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 263,608
Affiliate revenue	0	$ 0
Other operations	13,152
Revenue unrelated to contracts with customers	13,152
Total retail revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	204,510
Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	91,390
Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	66,695
Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	37,386
Other retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,801
Surcharge
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,238
Wholesale, net
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	41,410
Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17,644
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	44
Cleco Power | Other
Disaggregation of Revenue [Line Items]
Reserve for capital expenditures	1,900
Operating Segments | Cleco Power
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	266,027
Affiliate revenue	208	219
Other operations	13,152
Revenue unrelated to contracts with customers	13,360
Operating Segments | Cleco Power | Total retail revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	204,510
Operating Segments | Cleco Power | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	91,390
Operating Segments | Cleco Power | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	66,695
Operating Segments | Cleco Power | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	37,386
Operating Segments | Cleco Power | Other retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,801
Operating Segments | Cleco Power | Surcharge
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5,238
Operating Segments | Cleco Power | Wholesale, net
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	43,830
Operating Segments | Cleco Power | Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17,644
Operating Segments | Cleco Power | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	43
Operating Segments | OTHER
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(2,419)
Affiliate revenue	15,669	14,734
Other operations	0
Revenue unrelated to contracts with customers	15,669
Operating Segments | OTHER | Total retail revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Operating Segments | OTHER | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Operating Segments | OTHER | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Operating Segments | OTHER | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Operating Segments | OTHER | Other retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Operating Segments | OTHER | Surcharge
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Operating Segments | OTHER | Wholesale, net
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(2,420)
Operating Segments | OTHER | Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Operating Segments | OTHER | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1
ELIMINATIONS
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Affiliate revenue	(15,877)	(14,953)
Other operations	0
Revenue unrelated to contracts with customers	(15,877)
ELIMINATIONS | Total retail revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Other retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Surcharge
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Wholesale, net
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
ELIMINATIONS | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0
Cleco Power
Disaggregation of Revenue [Line Items]
Affiliate revenue	208	$ 219
SSR | Cleco Power | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 3,200