Retirement, Other Postretirement Benefits, And Defined Contribution Plans Expected Employer Contributions (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Other Postretirement Benefits Plan [Member]
Change in Plan Assets
Expected Employer Contributions	$ 39,900
Entergy Arkansas [Member] | Pension Plans, Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	66,649
Entergy Arkansas [Member] | Other Postretirement Benefits Plan [Member]
Change in Plan Assets
Expected Employer Contributions	517
Entergy Louisiana [Member] | Pension Plans, Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	59,882
Entergy Louisiana [Member] | Other Postretirement Benefits Plan [Member]
Change in Plan Assets
Expected Employer Contributions	15,600
Entergy Mississippi [Member] | Pension Plans, Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	13,715
Entergy Mississippi [Member] | Other Postretirement Benefits Plan [Member]
Change in Plan Assets
Expected Employer Contributions	130
Entergy New Orleans [Member] | Pension Plans, Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	5,395
Entergy New Orleans [Member] | Other Postretirement Benefits Plan [Member]
Change in Plan Assets
Expected Employer Contributions	175
Entergy Texas [Member] | Pension Plans, Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	6,955
Entergy Texas [Member] | Other Postretirement Benefits Plan [Member]
Change in Plan Assets
Expected Employer Contributions	66
System Energy [Member] | Pension Plans, Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	18,663
System Energy [Member] | Other Postretirement Benefits Plan [Member]
Change in Plan Assets
Expected Employer Contributions	$ 22