Decommissioning Trust Funds (Securities Held) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Total	$ 1,707.0	$ 1,655.0
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	160.0	201.0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	8.0	4.0
Total	1,707.0	1,655.0
Entergy Arkansas [Member]
Debt Securities, Available-for-sale [Line Items]
Total	479.4	470.7
Entergy Arkansas [Member] | Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	56.8	69.3
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0.9	0.2
Total	479.4	470.7
Entergy Louisiana [Member]
Debt Securities, Available-for-sale [Line Items]
Total	759.0	725.1
Entergy Louisiana [Member] | Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	50.4	67.5
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	5.4	3.5
Total	759.0	725.1
System Energy [Member]
Debt Securities, Available-for-sale [Line Items]
Total	468.1	459.7
System Energy [Member] | Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	52.6	63.7
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	2.1	0.7
Total	$ 468.1	$ 459.7