Asset Retirement Obligations (Details 1) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cumulative decommissioning and retirement cost liabilities and expenses
Accretion	$ 190,595,000	$ 211,736,000	$ 199,063,000
Entergy Wholesale Commodities [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	1,420,000,000	1,320,600,000
Accretion	115,600,000	107,600,000
Change in Cash Flow Estimate	(34,100,000)
Spending	(8,600,000)	(8,200,000)
Asset Retirement Obligation, Ending balance	1,492,900,000	1,420,000,000
Entergy Arkansas
Cumulative decommissioning and retirement cost liabilities and expenses
Accretion	38,064,000	35,790,000	34,575,000
Entergy Arkansas | Utility [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	602,200,000	566,400,000
Accretion	38,000,000	35,800,000
Asset Retirement Obligation, Ending balance	640,200,000	602,200,000
Entergy Gulf States Louisiana
Cumulative decommissioning and retirement cost liabilities and expenses
Accretion	14,189,000	13,400,000	13,591,000
Entergy Gulf States Louisiana | Utility [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	339,900,000	321,200,000
Accretion	19,900,000	18,700,000
Asset Retirement Obligation, Ending balance	359,800,000	339,900,000
Entergy Louisiana [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Accretion	24,658,000	22,960,000	21,377,000
Entergy Louisiana [Member] | Utility [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	321,200,000	298,200,000
Accretion	24,600,000	23,000,000
Asset Retirement Obligation, Ending balance	345,800,000	321,200,000
Entergy Mississippi [Member] | Utility [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	5,400,000	5,100,000
Accretion	300,000	300,000
Asset Retirement Obligation, Ending balance	5,700,000	5,400,000
Entergy New Orleans [Member] | Utility [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	3,400,000	3,200,000
Accretion	200,000	200,000
Spending	(700,000)
Asset Retirement Obligation, Ending balance	2,900,000	3,400,000
Entergy Texas [Member] | Utility [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	3,600,000	3,400,000
Accretion	300,000	200,000
Asset Retirement Obligation, Ending balance	3,900,000	3,600,000
System Energy [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Accretion	31,460,000	31,374,000	29,451,000
System Energy [Member] | Utility [Member]
Cumulative decommissioning and retirement cost liabilities and expenses
Asset Retirement Obligation, Beginning Balance	452,800,000	421,400,000
Accretion	31,500,000	31,400,000
Change in Cash Flow Estimate	(38,900,000)
Asset Retirement Obligation, Ending balance	$ 445,400,000	$ 452,800,000