Retirement, Other Postretirement Benefits, And Defined Contribution Plans (One Percentage Point Change In Assumed Health Care Cost Trend Rate) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
1 Percentage Point Increase, Impact on the APBO	$ 109,954
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	7,310
1 Percentage Point Decrease, Impact on the APBO	(92,504)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(5,970)
Entergy Arkansas [Member]
1 Percentage Point Increase, Impact on the APBO	14,480
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	908
1 Percentage Point Decrease, Impact on the APBO	(12,259)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(748)
Entergy Louisiana [Member]
1 Percentage Point Increase, Impact on the APBO	24,987
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	1,769
1 Percentage Point Decrease, Impact on the APBO	(21,017)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(1,443)
Entergy Mississippi [Member]
1 Percentage Point Increase, Impact on the APBO	6,085
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	420
1 Percentage Point Decrease, Impact on the APBO	(5,122)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(343)
Entergy New Orleans [Member]
1 Percentage Point Increase, Impact on the APBO	2,763
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	179
1 Percentage Point Decrease, Impact on the APBO	(2,363)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(148)
Entergy Texas [Member]
1 Percentage Point Increase, Impact on the APBO	8,561
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	482
1 Percentage Point Decrease, Impact on the APBO	(7,230)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(397)
System Energy [Member]
1 Percentage Point Increase, Impact on the APBO	4,876
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	364
1 Percentage Point Decrease, Impact on the APBO	(4,048)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	$ (294)