Decommissioning Trust Funds (Available For Sale Securities Continuous Unrealized Loss Position Fair Value) (Details) - Debt Securities [Member] - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	$ 583.0	$ 840.0
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	922.0	666.0
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value	1,505.0	1,506.0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	21.0	63.0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	151.0	138.0
Debt Securities, Available-for-sale, Unrealized Loss Position	172.0	201.0
Entergy Arkansas [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	75.0	197.6
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	379.7	260.1
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value	454.7	457.7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	2.2	18.8
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	60.2	50.5
Debt Securities, Available-for-sale, Unrealized Loss Position	62.4	69.3
Entergy Louisiana [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	312.5	409.9
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	302.5	207.5
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value	615.0	617.4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	9.5	24.6
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	44.6	42.9
Debt Securities, Available-for-sale, Unrealized Loss Position	54.1	67.5
System Energy [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	195.8	231.9
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	239.4	198.0
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value	435.2	429.9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	9.5	19.2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	45.6	44.5
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 55.1	$ 63.7