Long - Term Debt (Narrative) (Details) $ in Thousands	1 Months Ended									12 Months Ended
	Jan. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jul. 31, 2015 USD ($)	May. 31, 2015 USD ($)	Sep. 30, 2011 USD ($)	Aug. 31, 2010 USD ($)	Jun. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)	Apr. 30, 2007 USD ($)	Dec. 31, 2015 USD ($) installment	Sep. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)	Nov. 30, 2009 USD ($)	Jun. 30, 2007 USD ($)
Debt Instrument [Line Items]
Number of years of non-utility nuclear business liability for additional liability, in accordance with the purchase agreement										10 years
Year One		$ 204,079								$ 204,079
Year Two		766,451								766,451
Year Three		822,690								822,690
Year Four		768,588								768,588
Year Five		1,631,181								1,631,181
Bonds issued to recover cost		774,696								$ 774,696		$ 776,817
System Energy [Member]
Debt Instrument [Line Items]
Minimum rate of equity capital										35.00%
Year One		0								$ 0
Year Two		50,000								50,000
Year Three		85,000								85,000
Year Four		0								0
Year Five		0								0
Entergy Arkansas [Member]
Debt Instrument [Line Items]
Carrying costs on issuance of bonds to recover storm damage restoration costs							$ 11,500
Up front financing costs on issuance of bonds to recover storm damage restoration costs							$ 4,600
Value of non interest bearing first mortgage bonds						$ 124,100
Coupon rate of storm cost recovery bonds						2.30%
Year One		55,000								55,000
Year Two		114,700								114,700
Year Three		0								0
Year Four		0								0
Year Five		0								0
Bonds issued to recover cost		61,249								61,249		74,161
Entergy Louisiana [Member]
Debt Instrument [Line Items]
Carrying costs on issuance of bonds to recover storm damage restoration costs					$ 207,200
Coupon rate of storm cost recovery bonds					2.04%
Year One		20,600								20,600
Year Two		100,000								100,000
Year Three		675,000								675,000
Year Four		0								0
Year Five		320,000								320,000
Bonds issued to recover cost		120,549								120,549		140,782
Entergy New Orleans [Member]
Debt Instrument [Line Items]
Up front financing costs on issuance of bonds to recover storm damage restoration costs				$ 3,000
Year One		4,973								4,973
Year Two		2,104								2,104
Year Three		2,077								2,077
Year Four		1,979								1,979
Year Five		26,838								26,838
Cost recovered through issuance of securitization bonds				98,700
Bonds issued to recover cost		95,867								95,867		0
Issuance Of Debt			$ 98,700
Amount of Hurricane Issac storm cost to be recovered through securitization				31,800
Replenishment amount for storm reserve spending				$ 63,900
Entergy Texas [Member]
Debt Instrument [Line Items]
Year One		0								0
Year Two		0								0
Year Three		49,614								49,614
Year Four		617,462								617,462
Year Five		0								0
Bonds issued to recover cost		497,030								497,030		$ 561,874
Hurricane Rita [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year One		26,000								26,000
Year Two		27,600								27,600
Year Three		29,200								29,200
Year Four		30,900								30,900
Year Five		32,800								32,800
Cost recovered through issuance of securitization bonds									$ 353,000
Amount of storm cost recovery bonds for transaction costs									6,000
Deferred income tax benefits									$ 32,000
Bonds issued to recover cost		329,500								329,500				$ 329,500
Hurricane Ike And Hurricane Gustav [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year One		42,600								42,600
Year Two		44,100								44,100
Year Three		45,800								45,800
Year Four		47,600								47,600
Year Five		49,800								49,800
Cost recovered through issuance of securitization bonds								$ 566,400
Bonds issued to recover cost		545,900								545,900			$ 545,900
Tranche A-3 (5.93%) Due June 2022 [Member] | Hurricane Rita [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year Four		4,000								4,000
Bonds issued to recover cost		114,400								114,400
Tranche A-1 (5.51%) Due October 2013 [Member] | Hurricane Rita [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Bonds issued to recover cost		93,500								93,500
Tranche A-1 (2.12%) Due February 2016 [Member] | Hurricane Ike And Hurricane Gustav [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Bonds issued to recover cost		182,500								182,500
Tranche A-2 (5.79%) Due October 2018 [Member] | Hurricane Rita [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year Four		23,600								23,600
Bonds issued to recover cost		121,600								121,600
Tranche A-2 (3.65%) Due August 2019 [Member] | Hurricane Ike And Hurricane Gustav [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year Five		30,800								30,800
Bonds issued to recover cost		144,800								144,800
Tranche A-3 (4.38%) Due November 2023 [Member] | Hurricane Ike And Hurricane Gustav [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year Five		15,000								15,000
Bonds issued to recover cost		218,600								$ 218,600
Tranche A One Two Point Six Seven Percent Due June Two Thousand Twenty Seven [Member] | Entergy New Orleans [Member]
Debt Instrument [Line Items]
Coupon rate of storm cost recovery bonds			2.67%
Year One											$ 11,400
Year Two											10,600
Year Three											11,000
Year Four											11,200
Year Five											$ 11,600
Note Payable To NYPA [Member]
Debt Instrument [Line Items]
Number of annual installments of notes commencing one year from date of closing | installment										7
Annual installments of Notes payable commencing one year from the date of the closing										$ 108,000
Number of annual installments of notes commencing eight years from the date of closing | installment										8
Annual installments of Notes payable commencing eight years from the date of the closing		20,000								$ 20,000
Implicit interest rate on notes issued										4.80%
Per year additional liability of non-utility nuclear business, in accordance with the purchase agreement										$ 10,000
Write down of debt liability		$ 26,400
Securitization Bonds, 2.30% Series Senior Secured, Due August 2021 [Member] | Entergy Arkansas [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.30%								2.30%		2.30%
Year One		$ 13,400								$ 13,400
Year Two		13,800								13,800
Year Three		14,100								14,100
Year Four		14,400								14,400
Year Five		$ 7,300								$ 7,300
Debt Instrument, Interest Rate, Stated Percentage		2.30%								2.30%		2.30%
Securitization Bonds, 2.04% Series Senior Secured, Due June 2021 [Member] | Entergy Louisiana [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.04%								2.04%		2.04%
Year One		$ 21,600								$ 21,600
Year Two		21,700								21,700
Year Three		22,300								22,300
Year Four		22,700								22,700
Year Five		$ 23,200								$ 23,200
Debt Instrument, Interest Rate, Stated Percentage		2.04%								2.04%		2.04%
Subsequent Event [Member] | Three Point Five Percent Series First Mortgage Bonds Due April Two Thousand Twenty Six [Member] | Entergy Arkansas [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.50%
Issuance Of Debt	$ 325,000
Debt Instrument, Interest Rate, Stated Percentage	3.50%
Subsequent Event [Member] | Mortgage Bonds Five Point Six Six Percent Series Due February Two Thousand Twenty Five [Member] | Entergy Arkansas [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	5.66%
Issuance Of Debt	$ 175,000
Debt Instrument, Interest Rate, Stated Percentage	5.66%