Revolving Credit Facilities, Lines Of Credit, Short-Term Borrowings, And Long-Term Debt (Notes Payable By Variable Interest Entities) (Details) - USD ($) $ in Millions	Oct. 31, 2020	Sep. 30, 2020
Three Point Four Two Percent Series J Notes Due April Two Thousand Twenty One [Member] | System Energy VIE [Member]
Notes payable by variable interest entities
Stated interest rate (percentage)		3.42%
Amount		$ 100
Three Point Six Five Percent Series L Notes Due July Two Thousand Twenty One [Member] | Entergy Arkansas VIE [Member]
Notes payable by variable interest entities
Stated interest rate (percentage)		3.65%
Amount		$ 90
Three Point One Seven Percent Series M Notes Due December Two Thousand Twenty Three [Member] | Entergy Arkansas VIE [Member]
Notes payable by variable interest entities
Stated interest rate (percentage)		3.17%
Amount		$ 40
Three Point Nine Two Percent Series H Dues February Two Thousand Twenty One [Member] | Entergy Louisiana Waterford VIE [Member]
Notes payable by variable interest entities
Stated interest rate (percentage)		3.92%
Amount		$ 40
Three Point Two Two Percent Series I Notes Due December Two Thousand Twenty Three [Domain] | Entergy Louisiana Waterford VIE [Member]
Notes payable by variable interest entities
Stated interest rate (percentage)		3.22%
Amount		$ 20
Two Point Fifty One Percent Series V Notes Due June 2027 | Entergy Louisiana River Bend VIE [Member]
Notes payable by variable interest entities
Stated interest rate (percentage)		2.51%
Amount		$ 70
Subsequent Event [Member] | 2.05% Series K Intermediate term secured notes [Member] | System Energy VIE [Member]
Notes payable by variable interest entities
Stated interest rate (percentage)	2.05%
Amount	$ 90