Rate and Regulatory Matters (Estimated Hurricane Isaac Total Restoration Costs For Repair And Or Replacement Of Electric Facilities) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Entergy Arkansas [Member]
Estimated Hurricane Isaac Total Restoration Costs	$ 10.0
Minimum [Member] | Parent Company [Member]
Estimated Hurricane Isaac Total Restoration Costs	400.0
Minimum [Member] | Entergy Gulf States Louisiana [Member]
Estimated Hurricane Isaac Total Restoration Costs	70.0
Minimum [Member] | Entergy Louisiana [Member]
Estimated Hurricane Isaac Total Restoration Costs	240.0
Minimum [Member] | Entergy Mississippi [Member]
Estimated Hurricane Isaac Total Restoration Costs	30.0
Minimum [Member] | Entergy New Orleans
Estimated Hurricane Isaac Total Restoration Costs	50.0
Maximum [Member] | Parent Company [Member]
Estimated Hurricane Isaac Total Restoration Costs	500.0
Maximum [Member] | Entergy Gulf States Louisiana [Member]
Estimated Hurricane Isaac Total Restoration Costs	90.0
Maximum [Member] | Entergy Louisiana [Member]
Estimated Hurricane Isaac Total Restoration Costs	300.0
Maximum [Member] | Entergy Mississippi [Member]
Estimated Hurricane Isaac Total Restoration Costs	40.0
Maximum [Member] | Entergy New Orleans
Estimated Hurricane Isaac Total Restoration Costs	$ 60.0