Rate And Regulatory Matters (Correction Of Regulatory Asset For Income Taxes, Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Regulatory asset for income taxes - net	$ 752,696	$ 742,030
Accumulated deferred income taxes - current	15,004	13,109
Accumulated deferred income taxes and taxes accrued	8,348,976	8,311,756
Member's equity	9,307,076	9,291,089	9,008,260	9,055,270
Entergy Arkansas [Member]
Regulatory asset for income taxes - net	78,572	80,751
Accumulated deferred income taxes - current	3,824	5,927
Accumulated deferred income taxes and taxes accrued	1,865,020	1,829,281
Member's equity	1,577,617	1,579,616	1,456,280	1,444,124
Entergy Gulf States Louisiana [Member]
Regulatory asset for income taxes - net	170,894	171,051
Accumulated deferred income taxes - current	40,640	22,249
Accumulated deferred income taxes and taxes accrued	1,414,707	1,403,195
Member's equity	1,291,008	1,383,004	1,341,351	1,333,776
Entergy Louisiana [Member]
Regulatory asset for income taxes - net	196,216	193,114
Accumulated deferred income taxes - current	3,533	0
Accumulated deferred income taxes and taxes accrued	913,296	930,606
Member's equity	3,074,211	3,070,496	2,596,539	2,564,929
Entergy Mississippi [Member]
Regulatory asset for income taxes - net	62,936	63,614
Accumulated deferred income taxes - current	32	218
Accumulated deferred income taxes and taxes accrued	760,975	761,812
Member's equity	885,473	879,646	843,681	835,706
Entergy New Orleans
Accumulated deferred income taxes and taxes accrued	175,342	172,790
Member's equity	196,631	195,565	179,264	181,165
Entergy Texas [Member]
Regulatory asset for income taxes - net	130,490	131,287
Accumulated deferred income taxes and taxes accrued	971,241	1,009,081
Member's equity	855,068	854,146	901,100	899,355
System Energy [Member]
Regulatory asset for income taxes - net	124,604	126,503
Accumulated deferred income taxes - current	1,420	1,789
Accumulated deferred income taxes and taxes accrued	791,637	782,469
Member's equity	810,735	832,729	798,349	800,563
Member's Equity [Member] | Entergy Gulf States Louisiana [Member]
Member's equity	1,345,282	1,438,233	1,399,933	1,393,386
Member's Equity [Member] | Entergy Louisiana [Member]
Member's equity	$ 3,019,665	$ 3,016,628	$ 2,535,393	$ 2,504,436