Income Taxes (Summary Of Accrued Interest And Penalties Related To Unrecognized Tax Benefits) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accrued income tax interest and penalties	$ 96.4	$ 146.3	$ 99.0
Entergy Arkansas [Member]
Accrued income tax interest and penalties	15.2	21.8	11.4
Entergy Gulf States Louisiana [Member]
Accrued income tax interest and penalties	17.0	33.1	14.4
Entergy Louisiana [Member]
Accrued income tax interest and penalties	1.0	0.9	0.8
Entergy Mississippi [Member]
Accrued income tax interest and penalties	2.1	2.4	1.7
Entergy New Orleans [Member]
Accrued income tax interest and penalties	0.9	0.1	2.4
Entergy Texas [Member]
Accrued income tax interest and penalties	0.8	0.7	0.1
System Energy [Member]
Accrued income tax interest and penalties	$ 19.0	$ 33.2	$ 18.5