Asset Retirement Obligations (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Receivables recorded for beneficial interests in decommissioning trust funds						$ 1,500,000
Decommissioning Fund Investments		$ 7,211,993			$ 5,723,897
Asset Retirement Obligation		6,185,800			6,706,800		$ 4,790,200
Entergy Louisiana [Member]
Decommissioning Fund Investments		1,312,073			1,140,707
Asset Retirement Obligation		1,140,500			1,082,700		1,027,900
System Energy [Member]
Reduction in decommissioning liability				$ 35,900
Decommissioning Fund Investments		905,686			780,496
Asset Retirement Obligation		861,700			854,200		803,400
Entergy Wholesale Commodities [Member]
Asset Retirement Obligation		3,183,300			3,827,400		2,069,500
Entergy Arkansas [Member]
Decommissioning Fund Investments		944,890			834,735
Asset Retirement Obligation		$ 981,200			924,400		$ 872,300
Vermont Yankee [Member] | Entergy Wholesale Commodities [Member]
Spent Nuclear Fuel Obligation, Noncurrent								$ 225,000
FitzPatrick [Member] | Entergy Wholesale Commodities [Member]
Present Value Of The Difference Between The Stipulated Contract Amount For Decommissioning The Plants Less The Decommissioning Cost	$ 335,000
Present Value Of The Difference Between The Stipulated Contract Amount For Decommissioning The Plants Less The Decommissioning Cost After Impairment	131,000
Change in Contract Amount For Decommissioning The Plants Less The Decommissioning Cost	$ 204,000
FitzPatrick [Member] | NYPA [Member]
Decommissioning Fund Investments					785,000
Palisades [Member] | Entergy Wholesale Commodities [Member]
Reduction in decommissioning liability			$ 68,700
Increase in decommissioning liability					129,000
Indian Point Energy Center Units [Member] | Entergy Wholesale Commodities [Member]
Increase in decommissioning liability					392,000
Indian Point 3 [Member] | NYPA [Member]
Decommissioning Fund Investments					$ 719,000