Asset Retirement Obligations (Difference Between Estimated Incurred Removal Costs And Estimated Removal Costs Recovered In Rates) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Entergy Arkansas [Member]
Asset Retirement Obligations [Line Items]
Regulatory Assets	$ 18.6
Regulatory Liabilities		(12.2)
Entergy Gulf States Louisiana [Member]
Asset Retirement Obligations [Line Items]
Regulatory Liabilities	(35.3)	(22.0)
Entergy Louisiana [Member]
Asset Retirement Obligations [Line Items]
Regulatory Liabilities	(37.0)	(9.2)
Entergy Mississippi [Member]
Asset Retirement Obligations [Line Items]
Regulatory Assets	64.3	57.4
Entergy New Orleans [Member]
Asset Retirement Obligations [Line Items]
Regulatory Assets	34.9	29.9
Entergy Texas [Member]
Asset Retirement Obligations [Line Items]
Regulatory Assets	15.1	11.5
System Energy [Member]
Asset Retirement Obligations [Line Items]
Regulatory Assets	$ 56.0	$ 56.8