Fair Value Accounting - Net Changes in Net Fair Value of FTR Assets and Liabilities Classified as Level 3 (Details) - Price Risk Derivative - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 7,810	$ 4,283	$ 22,887	$ 7,044
Unrealized (losses) gains	(2,909)	2,420	(3,862)	2,420
Purchases	20,607	25,112	25,844	25,483
Settlements	(10,843)	(6,682)	(30,204)	(9,814)
Ending balance	14,665	25,133	14,665	25,133
CLECO POWER
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	4,812	4,283	22,887	7,044
Unrealized (losses) gains	(2,552)	2,420	(2,552)	2,420
Purchases	18,542	25,112	19,828	25,483
Settlements	(6,892)	(6,682)	(26,253)	(9,814)
Ending balance	$ 13,910	$ 25,133	$ 13,910	$ 25,133