v3.26.1
Decommissioning Trust Funds (Narrative) (Details) - USD ($)
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Decommissioning Trust Funds (Textual) [Abstract]          
Debt Securities, Available-for-Sale, Amortized Cost $ 2,508,000,000   $ 2,508,000,000   $ 2,219,000,000
Average Coupon Rate of Debt Securities Percentage 4.25%   4.25%    
Average Duration of Debt Securities in Years     6 years 2 months 12 days    
Average Maturity of Debt Securities, Years     10 years 9 months 10 days    
Proceeds from Sale of Debt Securities, Available-for-Sale $ 209,000,000 $ 227,000,000 $ 368,000,000 $ 489,000,000  
Debt Securities, Available-for-Sale, Realized Gain 1,000,000 1,000,000 2,000,000 2,000,000  
Debt Securities, Available-for-Sale, Realized Loss 6,000,000 4,000,000 8,000,000 8,000,000  
Equity Securities, FV-NI, Unrealized Gain (Loss) 532,000,000   351,000,000    
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss 0   0   0
Entergy Arkansas [Member]          
Decommissioning Trust Funds (Textual) [Abstract]          
Debt Securities, Available-for-Sale, Amortized Cost $ 710,700,000   $ 710,700,000   620,700,000
Average Coupon Rate of Debt Securities Percentage 3.87%   3.87%    
Average Duration of Debt Securities in Years     6 years 3 months 14 days    
Average Maturity of Debt Securities, Years     8 years 6 months 29 days    
Proceeds from Sale of Debt Securities, Available-for-Sale $ 7,200,000 0 $ 11,000,000.0 0  
Debt Securities, Available-for-Sale, Realized Gain 100,000 0 100,000 0  
Equity Securities, FV-NI, Unrealized Gain (Loss) 153,500,000   101,800,000    
Entergy Louisiana [Member]          
Decommissioning Trust Funds (Textual) [Abstract]          
Debt Securities, Available-for-Sale, Amortized Cost $ 1,100,000,000   $ 1,100,000,000   994,600,000
Average Coupon Rate of Debt Securities Percentage 4.46%   4.46%    
Average Duration of Debt Securities in Years     6 years 25 days    
Average Maturity of Debt Securities, Years     11 years 11 months 8 days    
Proceeds from Sale of Debt Securities, Available-for-Sale $ 113,900,000 71,500,000 $ 189,600,000 181,500,000  
Percentage Interest in River Bend     30.00%    
Debt Securities, Available-for-Sale, Realized Gain 200,000 100,000 $ 600,000 200,000  
Debt Securities, Available-for-Sale, Realized Loss 4,600,000 2,400,000 6,100,000 4,000,000.0  
Equity Securities, FV-NI, Unrealized Gain (Loss) 229,500,000   150,300,000    
System Energy [Member]          
Decommissioning Trust Funds (Textual) [Abstract]          
Debt Securities, Available-for-Sale, Amortized Cost $ 697,800,000   $ 697,800,000   $ 603,700,000
Average Coupon Rate of Debt Securities Percentage 4.29%   4.29%    
Average Duration of Debt Securities in Years     6 years 3 months 29 days    
Average Maturity of Debt Securities, Years     11 years 2 months 12 days    
Proceeds from Sale of Debt Securities, Available-for-Sale $ 87,700,000 155,300,000 $ 166,700,000 307,600,000  
Debt Securities, Available-for-Sale, Realized Gain 300,000 800,000 600,000 1,300,000  
Debt Securities, Available-for-Sale, Realized Loss 1,400,000 $ 1,400,000 2,100,000 $ 4,000,000.0  
Equity Securities, FV-NI, Unrealized Gain (Loss) $ 148,600,000   $ 98,400,000