Decommissioning Trust Funds (Available For Sale Securities Continuous Unrealized Loss Position Fair Value) (Details) - Debt Securities [Member] - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Unrealized Loss Position	$ 134.0	$ 201.0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	134.0	840.0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	999.0	666.0
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value	1,133.0	1,506.0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	6.0	63.0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	128.0	138.0
Entergy Arkansas [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Unrealized Loss Position	53.6	69.3
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	22.5	197.6
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	403.4	260.1
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value	425.9	457.7
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	0.4	18.8
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	53.2	50.5
Entergy Louisiana [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Unrealized Loss Position	37.4	67.5
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	69.8	409.9
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	356.1	207.5
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value	425.9	617.4
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	0.9	24.6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	36.5	42.9
System Energy [Member]
Debt Securities, Available-for-Sale [Line Items]
Debt Securities, Available-for-Sale, Unrealized Loss Position	42.5	63.7
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	42.1	231.9
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	239.1	198.0
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value	281.2	429.9
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	4.5	19.2
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 38.0	$ 44.5