Disclosures about Segments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($) entity	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of transmission interconnection facility subsidiaries | entity	2
Revenue [Abstract]
Electric operations	$ 262,211	$ 234,056
Other operations	22,196	16,880
Electric customer credits	(7,647)	(435)
Affiliate revenue	0	0
Operating revenue, net	276,760	250,501
Depreciation and amortization	42,507	40,851
Interest charges	31,157	31,718
Interest income	783	312
Federal and state income tax expense (benefit)	2,862	3,107
Net income (loss)	10,861	6,292
Additions to property, plant, and equipment	64,133	47,890
Equity investment in investee	18,172		$ 18,172
Goodwill	1,490,797		1,490,797
Total Segment Assets	6,309,981		6,278,382
Operating Segments | Cleco Power
Revenue [Abstract]
Electric operations	264,631	237,553
Other operations	22,195	16,365
Electric customer credits	(7,647)	(435)
Affiliate revenue	208	219
Operating revenue, net	279,387	253,702
Depreciation and amortization	40,388	38,758
Interest charges	17,656	18,104
Interest income	641	266
Federal and state income tax expense (benefit)	7,997	9,855
Net income (loss)	26,004	17,854
Additions to property, plant, and equipment	63,343	46,744
Equity investment in investee	18,172		18,172
Goodwill	1,490,797		1,490,797
Total Segment Assets	5,722,284		5,679,538
Operating Segments | OTHER
Revenue [Abstract]
Electric operations	(2,420)	(3,497)
Other operations	1	515
Electric customer credits	0	0
Affiliate revenue	15,669	14,734
Operating revenue, net	13,250	11,752
Depreciation and amortization	2,119	2,093
Interest charges	13,549	13,681
Interest income	190	113
Federal and state income tax expense (benefit)	(5,135)	(6,748)
Net income (loss)	(15,142)	(11,562)
Additions to property, plant, and equipment	790	1,146
Equity investment in investee	0		0
Goodwill	0		0
Total Segment Assets	618,513		619,943
ELIMINATIONS
Revenue [Abstract]
Electric operations	0	0
Other operations	0	0
Electric customer credits	0	0
Affiliate revenue	(15,877)	(14,953)
Operating revenue, net	(15,877)	(14,953)
Depreciation and amortization	0	0
Interest charges	(48)	(67)
Interest income	(48)	(67)
Federal and state income tax expense (benefit)	0	0
Net income (loss)	(1)	0
Additions to property, plant, and equipment	0	$ 0
Equity investment in investee	0		0
Goodwill	0		0
Total Segment Assets	$ (30,816)		$ (21,099)