Asset Retirement Obligations (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Asset Retirement Obligation			$ 4,505.8	$ 4,271.5	$ 4,757.1
Asset Retirement Obligation, Revision of Estimate			14.9	(0.5)
Entergy Louisiana [Member]
Asset Retirement Obligation			1,836.2	1,736.8	1,653.2
Asset Retirement Obligation, Revision of Estimate			10.8	2.8
Entergy Louisiana [Member] | Big Cajun 2 [Member]
Asset Retirement Obligation, Revision of Estimate		$ 2.8
Entergy Louisiana [Member] | River Bend [Member]
Asset Retirement Obligation, Revision of Estimate	$ 10.8
System Energy [Member]
Asset Retirement Obligation			1,084.2	1,042.5	1,007.6
Asset Retirement Obligation, Revision of Estimate			0.0	(5.4)
System Energy [Member] | Grand Gulf [Member]
Asset Retirement Obligation, Revision of Estimate		5.4
Entergy Arkansas [Member]
Asset Retirement Obligation			1,560.1	1,472.7	1,390.4
Asset Retirement Obligation, Revision of Estimate			0.0	0.0
Entergy Mississippi [Member]
Asset Retirement Obligation			8.2	7.8	10.3
Asset Retirement Obligation, Revision of Estimate			0.0	0.0
Entergy Texas [Member]
Asset Retirement Obligation			11.7	11.1	8.5
Asset Retirement Obligation, Revision of Estimate			0.0	2.1
Entergy Texas [Member] | Big Cajun 2 [Member]
Asset Retirement Obligation, Revision of Estimate		$ 2.1
Entergy New Orleans [Member]
Asset Retirement Obligation			4.6	0.0	$ 4.0
Asset Retirement Obligation, Revision of Estimate			$ 4.1	$ 0.0