Disclosures about Segments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Revenue
Electric operations	$ 365,466	$ 294,213	$ 678,416	$ 556,424
Other operations	42,367	18,685	81,764	40,881
Affiliate revenue	0	0	0	0
Electric customer credits	(9,960)	(13,637)	(18,120)	(21,284)
Operating revenue, net	397,873	299,261	742,060	576,021
Depreciation and amortization	51,535	41,807	101,391	84,314
Interest income	1,275	1,427	2,767	2,211
Interest charges, net	35,840	31,909	69,839	63,067
Federal and state income tax expense (benefit)	12,281	7,665	18,267	10,528
Net income (loss)	44,746	25,839	65,303	36,700
Additions to property, plant, and equipment			151,463	135,702
Equity investment in investees	18,172		18,172		$ 18,172
Goodwill	1,490,797		1,490,797		1,490,797
Total segment assets	7,505,011		7,505,011		6,436,814
Operating Segments | CLECO POWER
Revenue
Electric operations	265,924	296,633	523,100	561,264
Other operations	15,404	18,685	34,833	40,880
Affiliate revenue	337	220	637	428
Electric customer credits	(8,693)	(13,637)	(16,853)	(21,284)
Operating revenue, net	272,972	301,901	541,717	581,288
Depreciation and amortization	39,330	39,720	81,707	80,109
Interest income	867	1,313	1,860	1,953
Interest charges, net	17,370	18,107	34,515	35,763
Federal and state income tax expense (benefit)	13,978	13,710	21,976	21,707
Net income (loss)	49,356	43,020	76,068	69,024
Additions to property, plant, and equipment			147,696	135,334
Equity investment in investees	18,172		18,172		18,172
Goodwill	1,490,797		1,490,797		1,490,797
Total segment assets	5,931,335		5,931,335		5,839,853
Operating Segments | CLECO CAJUN
Revenue
Electric operations	101,962		160,156
Other operations	29,917		49,883
Affiliate revenue	0		0
Electric customer credits	(1,267)		(1,267)
Operating revenue, net	130,612		208,772
Depreciation and amortization	10,136		15,546
Interest income	368		622
Interest charges, net	0		0
Federal and state income tax expense (benefit)	4,028		7,557
Net income (loss)	12,926		23,982
Additions to property, plant, and equipment			2,672
Equity investment in investees	0		0
Goodwill	0		0
Total segment assets	1,048,891		1,048,891
OTHER
Revenue
Electric operations	(2,420)	(2,420)	(4,840)	(4,840)
Other operations	0	0	2	1
Affiliate revenue	23,012	17,273	49,547	32,942
Electric customer credits	0	0	0	0
Operating revenue, net	20,592	14,853	44,709	28,103
Depreciation and amortization	2,070	2,086	4,139	4,205
Interest income	197	152	614	342
Interest charges, net	18,626	13,843	35,654	27,392
Federal and state income tax expense (benefit)	(5,725)	(6,045)	(11,265)	(11,180)
Net income (loss)	(17,537)	(17,182)	(34,747)	(32,324)
Additions to property, plant, and equipment			1,095	368
Equity investment in investees	0		0		0
Goodwill	0		0		0
Total segment assets	559,660		559,660		633,756
ELIMINATIONS
Revenue
Electric operations	0	0	0	0
Other operations	(2,954)	0	(2,954)	0
Affiliate revenue	(23,349)	(17,493)	(50,184)	(33,370)
Electric customer credits	0	0	0	0
Operating revenue, net	(26,303)	(17,493)	(53,138)	(33,370)
Depreciation and amortization	(1)	1	(1)	0
Interest income	(157)	(38)	(329)	(84)
Interest charges, net	(156)	(41)	(330)	(88)
Federal and state income tax expense (benefit)	0	0	(1)	1
Net income (loss)	1	$ 1	0	0
Additions to property, plant, and equipment			0	$ 0
Equity investment in investees	0		0		0
Goodwill	0		0		0
Total segment assets	$ (34,875)		$ (34,875)		$ (36,795)