Revolving Credit Facilities, Lines Of Credit And Short-Term Borrowings (Short-Term Borrowings And The Outstanding Short-Term Borrowings) (Details) $ in Millions	Dec. 31, 2019 USD ($)
Entergy Arkansas [Member]
Short-term borrowings and the outstanding short-term borrowings
Authorized	$ 250
Borrowings	22
Entergy Louisiana [Member]
Short-term borrowings and the outstanding short-term borrowings
Authorized	450
Borrowings	83
Entergy Mississippi [Member]
Short-term borrowings and the outstanding short-term borrowings
Authorized	175
Borrowings	0
Entergy New Orleans [Member]
Short-term borrowings and the outstanding short-term borrowings
Authorized	150
Borrowings	0
Entergy Texas [Member]
Short-term borrowings and the outstanding short-term borrowings
Authorized	200
Borrowings	0
System Energy [Member]
Short-term borrowings and the outstanding short-term borrowings
Authorized	200
Borrowings	$ 0