Decommissioning Trust Funds (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Decommissioning Trust Funds (Textual) [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost	$ 2,456,000,000		$ 2,219,000,000
Average Coupon Rate of Debt Securities Percentage	4.17%
Average Duration of Debt Securities in Years	6 years 2 months 19 days
Average Maturity of Debt Securities, Years	10 years 6 months 29 days
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 159,000,000	$ 262,000,000
Debt Securities, Available-for-Sale, Realized Gain	1,000,000	1,000,000
Debt Securities, Available-for-Sale, Realized Loss	2,000,000	4,000,000
Equity Securities, FV-NI, Unrealized Gain (Loss)	185,000,000
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss	0		0
Entergy Arkansas [Member]
Decommissioning Trust Funds (Textual) [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost	$ 701,200,000		620,700,000
Average Coupon Rate of Debt Securities Percentage	3.75%
Average Duration of Debt Securities in Years	6 years 3 months 7 days
Average Maturity of Debt Securities, Years	8 years 6 months 18 days
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 3,800,000	0
Debt Securities, Available-for-Sale, Realized Gain	0	0
Debt Securities, Available-for-Sale, Realized Loss	100,000	0
Equity Securities, FV-NI, Unrealized Gain (Loss)	52,000,000
Entergy Louisiana [Member]
Decommissioning Trust Funds (Textual) [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost	$ 1,059,200,000		994,600,000
Average Coupon Rate of Debt Securities Percentage	4.44%
Average Duration of Debt Securities in Years	6 years 2 months 15 days
Average Maturity of Debt Securities, Years	12 years 2 months 15 days
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 75,700,000	110,000,000.0
Percentage Interest in River Bend	30.00%
Debt Securities, Available-for-Sale, Realized Gain	$ 400,000	100,000
Debt Securities, Available-for-Sale, Realized Loss	1,500,000	1,500,000
Equity Securities, FV-NI, Unrealized Gain (Loss)	82,600,000
System Energy [Member]
Decommissioning Trust Funds (Textual) [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost	$ 695,700,000		$ 603,700,000
Average Coupon Rate of Debt Securities Percentage	4.22%
Average Duration of Debt Securities in Years	6 years 2 months 4 days
Average Maturity of Debt Securities, Years	10 years 2 months 12 days
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 79,000,000.0	152,300,000
Debt Securities, Available-for-Sale, Realized Gain	300,000	600,000
Debt Securities, Available-for-Sale, Realized Loss	700,000	$ 2,700,000
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ 50,500,000