v3.26.1
Decommissioning Trust Funds (Schedule of Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value) (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]    
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value $ 1,122.0 $ 361.0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value 460.0 549.0
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value 1,582.0 910.0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months 17.0 3.0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer 39.0 42.0
Debt Securities, Available-for-Sale, Unrealized Loss Position 56.0 45.0
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 310.6 89.1
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value 183.8 211.1
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value 494.4 300.2
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months 5.1 0.6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer 15.0 13.6
Debt Securities, Available-for-Sale, Unrealized Loss Position 20.1 14.2
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 437.4 179.8
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value 150.0 196.6
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value 587.4 376.4
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months 5.3 1.6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer 9.1 13.4
Debt Securities, Available-for-Sale, Unrealized Loss Position 14.4 15.0
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 374.8 91.9
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value 126.0 141.7
Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value 500.8 233.6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months 6.1 1.1
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer 15.1 15.1
Debt Securities, Available-for-Sale, Unrealized Loss Position $ 21.2 $ 16.2