Commitments And Contingencies (Maximum Amounts Of Possible Assessments Per Occurrence) (Details) - Insurance-related Assessments [Member] $ in Thousands	Dec. 31, 2017 USD ($)
Entergy Arkansas [Member]
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 40,300
Entergy Louisiana [Member]
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	49,400
Entergy Mississippi [Member]
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	110
Entergy New Orleans [Member]
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	110
System Energy [Member]
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	22,300
Entergy Wholesale Commodities [Member]
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 0