Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Operating revenues	$ 2,508,523	$ 3,371,406	$ 2,713,231	$ 2,920,090	$ 2,831,318	$ 3,458,110	$ 2,996,650	$ 3,208,843	$ 11,513,251		$ 12,494,921		$ 11,390,947
Operating income (loss)	(254,300)	(965,016)	377,383	542,769	319,674	492,859	454,477	739,877	(299,165)		2,006,889		1,354,999
Consolidated net income (loss)	104,849	(718,233)	153,722	302,929	125,006	234,916	194,281	406,053	(156,734)	[1]	960,257	[1]	730,572	[1]
Net income (loss) attributable to Entergy Corporation	$ 99,573	$ (723,027)	$ 148,843	$ 298,050	$ 120,127	$ 230,037	$ 189,383	$ 401,174	$ (176,562)		$ 940,721		$ 711,902
Basic earnings per share (in usd per share)	$ 0.56	$ (4.04)	$ 0.83	$ 1.66	$ 0.67	$ 1.28	$ 1.06	$ 2.24	$ (0.99)		$ 5.24		$ 3.99
Diluted earnings per share (in usd per share)	$ 0.56	$ (4.04)	$ 0.83	$ 1.65	$ 0.66	$ 1.27	$ 1.05	$ 2.24	$ (0.99)		$ 5.22		$ 3.99
Entergy Arkansas [Member]
Operating revenues	$ 476,149	$ 714,353	$ 551,809	$ 511,253	$ 518,735	$ 627,153	$ 511,522	$ 514,981
Operating income (loss)	(21,635)	109,236	55,149	36,656	19,317	115,357	68,970	66,360	$ 179,406		$ 270,004		$ 305,060
Consolidated net income (loss)	(20,780)	55,662	21,525	17,865	1,037	62,980	29,005	28,370	74,272		121,392		161,948
Net income (loss) attributable to Entergy Corporation	(22,499)	53,944	19,807	16,147	(682)	61,262	27,287	26,652	67,399		114,519		155,075
Entergy Louisiana [Member]
Operating revenues	974,875	1,298,482	1,074,598	1,069,191	1,013,714	1,421,028	1,231,428	1,074,334	4,417,146		4,740,504		4,399,511
Operating income (loss)	47,052	294,436	191,068	185,776	82,381	257,293	170,526	167,633	718,332		677,833		602,731
Consolidated net income (loss)	24,409	187,140	108,981	126,109	55,978	179,356	105,838	104,850	446,639		446,022		414,126
Net income (loss) attributable to Entergy Corporation	24,410	185,290	107,037	124,165	54,036	177,412	103,872	102,906	440,902		438,226		406,351
Entergy Mississippi [Member]
Operating revenues	280,452	410,743	344,975	360,815	380,018	425,341	370,638	348,196
Operating income (loss)	24,717	74,264	58,086	54,839	61,162	9,403	59,063	57,132	211,906		186,760		190,230
Consolidated net income (loss)	4,918	36,576	26,279	24,935	28,882	(6,464)	26,564	25,839	92,708		74,821		82,159
Net income (loss) attributable to Entergy Corporation	4,211	35,869	25,572	24,228	28,175	(7,171)	25,857	25,132	89,880		71,993		79,331
Entergy New Orleans [Member]
Operating revenues	144,335	209,733	160,752	156,626	160,482	198,524	180,320	195,866	671,446		735,192		659,746
Operating income (loss)	9,337	34,734	20,154	20,745	317	28,396	13,421	15,822	84,970		57,956		30,770
Consolidated net income (loss)	3,575	19,163	10,895	11,292	398	15,950	6,406	8,276	44,925		31,030		12,608
Net income (loss) attributable to Entergy Corporation	3,333	18,922	10,654	11,051	156	15,709	6,165	8,035	43,960		30,065		11,643
Entergy Texas [Member]
Operating revenues	394,822	498,249	402,921	411,211	400,286	528,508	482,932	440,256
Operating income (loss)	8,944	86,624	44,064	44,013	29,590	82,911	53,158	43,056	183,645		208,715		174,133
Consolidated net income (loss)	(5,170)	43,314	14,890	16,591	3,495	39,559	18,585	13,165	69,625		74,804		57,881
System Energy [Member]
Operating revenues	157,366	155,899	163,101	156,039	170,716	172,151	163,830	157,667
Operating income (loss)	45,239	47,135	45,470	47,784	54,056	58,484	56,547	52,029	185,628		221,116		203,080
Consolidated net income (loss)	$ 38,702	$ 25,223	$ 21,860	$ 25,533	$ 19,054	$ 26,730	$ 25,931	$ 24,619	$ 111,318		$ 96,334		$ 113,664

[1] (a) Consolidated net income and preferred dividend requirements of subsidiaries for 2015, 2014, and 2013 include $14.9 million, $12.9 million, and $12 million, respectively, of preferred dividends on subsidiaries’ preferred stock without sinking fund that is not presented as equity.