Income Taxes - Current and Deferred Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Components of Income Tax Expense [Line Items]
Current federal income tax (benefit) expense	$ (2,634)	$ 1,600	$ 15,304
Deferred federal income tax expense	21,865	37,963	5,863
Amortization of accumulated deferred investment tax credits	(159)	(191)	(236)
Total federal income tax expense	19,072	39,372	20,931
Current state income tax expense	2,636	1,675	7,771
Deferred state income tax expense	14,010	2,118	680
Total state income tax expense	16,646	3,793	8,451
Total tax expense	35,718	43,165	29,382
Items charged or credited directly to member’s equity
Total tax expense (benefit) from items charged directly to member’s equity	(2,922)	(6,808)	1,868
Total federal and state income tax expense	32,796	36,357	31,250
Federal deferred
Items charged or credited directly to member’s equity
Total tax expense (benefit) from items charged directly to member’s equity	(2,202)	(5,130)	1,408
State deferred
Items charged or credited directly to member’s equity
Total tax expense (benefit) from items charged directly to member’s equity	(720)	(1,678)	460
CLECO POWER
Components of Income Tax Expense [Line Items]
Current federal income tax (benefit) expense	15,724	14,781	44,411
Deferred federal income tax expense	(5,033)	22,443	(9,033)
Amortization of accumulated deferred investment tax credits	(159)	(191)	(236)
Total federal income tax expense	10,532	37,033	35,142
Current state income tax expense	5,069	9,063	23,293
Deferred state income tax expense	11,198	(644)	(2,511)
Total state income tax expense	16,267	8,419	20,782
Total tax expense	26,799	45,452	55,924
Items charged or credited directly to member’s equity
Total tax expense (benefit) from items charged directly to member’s equity	(765)	(3,318)	1,058
Total federal and state income tax expense	26,034	42,134	56,982
CLECO POWER | Federal deferred
Items charged or credited directly to member’s equity
Total tax expense (benefit) from items charged directly to member’s equity	(576)	(2,500)	797
CLECO POWER | State deferred
Items charged or credited directly to member’s equity
Total tax expense (benefit) from items charged directly to member’s equity	$ (189)	$ (818)	$ 261