Decommissioning Trust Funds (Schedule of Investments Classified by Contractual Maturity Date) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five	$ 639,000	$ 574,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10	659,000	629,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Through 15	142,000	166,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 15 Through 20	210,000	218,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 20	472,000	424,000
Debt Securities, Available-for-Sale	2,155,000	2,047,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	33,000	36,000
Decommissioning Fund Investments	6,193,249	5,562,575
Entergy Arkansas [Member]
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five	150,600	142,500
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10	263,400	231,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Through 15	45,500	62,200
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 15 Through 20	52,800	62,800
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 20	72,900	48,800
Debt Securities, Available-for-Sale	609,300	579,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	24,100	31,700
Decommissioning Fund Investments	1,787,712	1,604,428
Entergy Louisiana [Member]
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five	230,300	188,200
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10	235,900	259,400
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Through 15	75,800	80,900
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 15 Through 20	111,200	106,100
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 20	295,600	269,100
Debt Securities, Available-for-Sale	951,400	908,100
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	2,600	4,400
Decommissioning Fund Investments	2,701,311	2,429,088
System Energy [Member]
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five	258,200	243,700
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10	159,200	138,900
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Through 15	20,300	22,700
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 15 Through 20	46,100	49,400
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 20	104,800	104,900
Debt Securities, Available-for-Sale	594,600	559,800
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	6,000	200
Decommissioning Fund Investments	$ 1,704,226	$ 1,529,059