Income Taxes Income Taxes (Reduction to Regulatory Liability Due to Return of Unprotected Excess ADIT (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Reduction to regulatory liability due to return of unprotected excess accumulated deferred income taxes	$ 17	$ 41
Entergy Arkansas [Member]
Reduction to regulatory liability due to return of unprotected excess accumulated deferred income taxes	0	8
Entergy Louisiana [Member]
Reduction to regulatory liability due to return of unprotected excess accumulated deferred income taxes	9	8
Entergy New Orleans [Member]
Reduction to regulatory liability due to return of unprotected excess accumulated deferred income taxes	1	0
Entergy Texas [Member]
Reduction to regulatory liability due to return of unprotected excess accumulated deferred income taxes	7	7
System Energy [Member]
Reduction to regulatory liability due to return of unprotected excess accumulated deferred income taxes	$ 0	$ 18