Retirement, Other Postretirement Benefits, And Defined Contribution Plans (Expected Employer Contributions) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Entergy Arkansas [Member] | Pension Plans Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	$ 34,945
Entergy Arkansas [Member] | Other Postretirement [Member]
Change in Plan Assets
Expected Employer Contributions	26,675
Entergy Gulf States Louisiana [Member] | Pension Plans Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	11,198
Entergy Gulf States Louisiana [Member] | Other Postretirement [Member]
Change in Plan Assets
Expected Employer Contributions	8,381
Entergy Louisiana [Member] | Pension Plans Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	20,731
Entergy Louisiana [Member] | Other Postretirement [Member]
Change in Plan Assets
Expected Employer Contributions	10,173
Entergy Mississippi [Member] | Pension Plans Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	7,969
Entergy Mississippi [Member] | Other Postretirement [Member]
Change in Plan Assets
Expected Employer Contributions	5,469
Entergy New Orleans [Member] | Pension Plans Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	3,959
Entergy New Orleans [Member] | Other Postretirement [Member]
Change in Plan Assets
Expected Employer Contributions	3,669
Entergy Texas [Member] | Pension Plans Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	6,666
Entergy Texas [Member] | Other Postretirement [Member]
Change in Plan Assets
Expected Employer Contributions	5,153
System Energy [Member] | Pension Plans Defined Benefit [Member]
Change in Plan Assets
Expected Employer Contributions	7,621
System Energy [Member] | Other Postretirement [Member]
Change in Plan Assets
Expected Employer Contributions	$ 4,090