Income Taxes (Schedule Of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross balance January 1	$ 3,909,855	$ 2,611,585	$ 4,736,785
Additions based on tax positions related to the current year	1,120,687	1,532,782	1,850,705
Additions for tax positions of prior years	283,683	368,404	59,815
Reductions for tax positions of prior years	(442,379)	(265,653)	(3,966,535)
Settlements	0	(337,263)	(68,227)
Lapse of statute of limitations	0	0	(958)
Gross balance at December 31	4,871,846	3,909,855	2,611,585
Unrecognized tax benefits net of unused tax attributes and payments	916,322	977,770	1,347,102
Remaining balances of unrecognized tax benefits, effective income tax rates	3,410,000	2,670,000	1,657,000
Net operating loss carryforwards	467,255	334,025
Offset to gross unrecognized tax benefits, credit and loss carryforward	(3,945,524)	(2,922,085)	(1,264,483)
Cash Paid To Taxing Authorities	10,000	10,000	0
Entergy Arkansas [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross balance January 1	2,503	25,445	362,912
Additions based on tax positions related to the current year	8,974	16,868	2,196
Additions for tax positions of prior years	3,682	2,463	1,057
Reductions for tax positions of prior years	(132,875)	(41,957)	(340,720)
Settlements		(316)	0
Gross balance at December 31	(117,716)	2,503	25,445
Unrecognized tax benefits net of unused tax attributes and payments	(117,716)	2,503	21,832
Net operating loss carryforwards	16,172	69,524
Offset to gross unrecognized tax benefits, credit and loss carryforward	0	0	(3,613)
Entergy Louisiana [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross balance January 1	2,440,339	1,690,661	1,205,929
Additions based on tax positions related to the current year	32,843	931,720	1,367,058
Additions for tax positions of prior years	235,331	157,586	7,992
Reductions for tax positions of prior years	(190,056)	(144,068)	(859,430)
Settlements		(195,560)	(30,888)
Gross balance at December 31	2,518,457	2,440,339	1,690,661
Unrecognized tax benefits net of unused tax attributes and payments	926,550	657,246	796,897
Net operating loss carryforwards	44	17,125
Offset to gross unrecognized tax benefits, credit and loss carryforward	(1,591,907)	(1,783,093)	(893,764)
Entergy Mississippi [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross balance January 1	12,206	19,482	20,144
Additions based on tax positions related to the current year	2,105	2,662	566
Additions for tax positions of prior years	1,267	336	8,140
Reductions for tax positions of prior years	(456)	(10,219)	0
Settlements		(55)	(9,368)
Gross balance at December 31	15,122	12,206	19,482
Unrecognized tax benefits net of unused tax attributes and payments	0	9,833	18,466
Net operating loss carryforwards	10,255	0
Offset to gross unrecognized tax benefits, credit and loss carryforward	(15,122)	(2,373)	(1,016)
Entergy New Orleans [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross balance January 1	166,230	53,897	53,763
Additions based on tax positions related to the current year	509,183	33,912	472
Additions for tax positions of prior years	13,364	129,784	48
Reductions for tax positions of prior years	(9,233)	(29,821)	(386)
Settlements		(21,542)	0
Gross balance at December 31	679,544	166,230	53,897
Unrecognized tax benefits net of unused tax attributes and payments	238,170	138,910	53,391
Net operating loss carryforwards	0	0
Offset to gross unrecognized tax benefits, credit and loss carryforward	(441,374)	(27,320)	(506)
Entergy Texas [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross balance January 1	15,946	13,462	17,264
Additions based on tax positions related to the current year	1,747	2,002	657
Additions for tax positions of prior years	3,115	2,888	2,914
Reductions for tax positions of prior years	(4,409)	(1,849)	(3,981)
Settlements		(557)	(3,392)
Gross balance at December 31	16,399	15,946	13,462
Unrecognized tax benefits net of unused tax attributes and payments	15,761	15,570	13,186
Net operating loss carryforwards	1,690	0
Offset to gross unrecognized tax benefits, credit and loss carryforward	(638)	(376)	(276)
System Energy [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross balance January 1	472,372	478,318	258,242
Additions based on tax positions related to the current year	909	5,318	472,304
Additions for tax positions of prior years	1,432	601	913
Reductions for tax positions of prior years	(29,202)	(10,266)	(253,141)
Settlements		(1,599)	0
Gross balance at December 31	445,511	472,372	478,318
Unrecognized tax benefits net of unused tax attributes and payments	432,975	382,344	344,707
Net operating loss carryforwards	0	0
Offset to gross unrecognized tax benefits, credit and loss carryforward	$ (12,536)	$ (90,028)	$ (133,611)