Property, Plant, And Equipment (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Construction expenditures in accounts payable	$ 367.0	$ 406.0
Entergy Arkansas [Member]
Construction expenditures in accounts payable	57.5	67.9
Entergy Louisiana [Member]
Construction expenditures in accounts payable	106.7	115.1
Entergy Mississippi [Member]
Construction expenditures in accounts payable	24.2	34.2
Entergy New Orleans [Member]
Construction expenditures in accounts payable	8.1	18.4
Entergy Texas [Member]
Construction expenditures in accounts payable	78.2	88.1
System Energy [Member]
Construction expenditures in accounts payable	$ 52.6	$ 23.2