Long - Term Debt (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended								3 Months Ended	12 Months Ended
	Dec. 31, 2015	Jul. 31, 2015	May 31, 2015	Sep. 30, 2011	Aug. 31, 2010	Jun. 30, 2010	Sep. 30, 2009	Apr. 30, 2007	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Nov. 30, 2009	Jun. 30, 2007
Debt Instrument [Line Items]
Year One										$ 760,000
Year Two										857,679
Year Three										898,500
Year Four										960,764
Year Five										1,304,431
Bonds issued to recover cost										$ 544,921	$ 661,175
System Energy [Member]
Debt Instrument [Line Items]
Minimum rate of equity capital										35.00%
Year One										$ 85,000
Year Two										50,000
Year Three										0
Year Four										0
Year Five										134,000
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										0
Year Two										24,900
Year Three										0
Year Four										520,764
Year Five										0
Bonds issued to recover cost										34,662	48,139
Entergy Louisiana [Member]
Debt Instrument [Line Items]
Value of non interest bearing first mortgage bonds					$ 207,200
Coupon rate of storm cost recovery bonds				2.04%
Year One										675,000
Year Two										102,010
Year Three										320,000
Year Four										240,000
Year Five										200,000
Bonds issued to recover cost										77,736	99,217
Entergy New Orleans [Member]
Debt Instrument [Line Items]
Up Front Financing Costs On Issuance Of Bonds To Recover Storm Damage Restoration Costs			$ 3,000
Coupon rate of storm cost recovery bonds		2.67%
Year One										2,077
Year Two										1,979
Year Three										26,838
Year Four										1,618
Year Five										1,326
Cost recovered through issuance of securitization bonds			98,700
Bonds issued to recover cost										74,419	84,776
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
Year Two										530,769
Year Three										0
Year Four										200,000
Year Five										110,431
Bonds issued to recover cost										358,104	$ 429,043
Hurricane Rita [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year One										29,200
Year Two										30,900
Year Three										32,800
Year Four										17,500
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
Hurricane Ike And Hurricane Gustav [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Year One										45,800
Year Two										47,600
Year Three										49,800
Year Four										52,000
Year Five										54,300
Cost recovered through issuance of securitization bonds							$ 566,400
Bonds issued to recover cost										545,900		$ 545,900
Tranche A-3 (5.93%) Due June 2022 [Member] | Hurricane Rita [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Bonds issued to recover cost										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
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
Tranche A-2 (5.79%) Due October 2018 [Member] | Hurricane Rita [Member] | Entergy Texas [Member]
Debt Instrument [Line Items]
Bonds issued to recover cost										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
Bonds issued to recover cost										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
Bonds issued to recover cost										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]
Year One										11,000
Year Two										11,200
Year Three										11,600
Year Four										11,900
Year Five										$ 12,200
Securitization Bonds, 2.04% Series Senior Secured, Due September 2023 [Member] | Entergy Louisiana [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage										2.04%	2.04%
Year One										$ 22,300
Year Two										22,700
Year Three										23,200
Year Four										$ 11,000
Debt Instrument, Interest Rate, Stated Percentage										2.04%	2.04%
Note Payable To NYPA [Member]
Debt Instrument [Line Items]
Write down of debt liability	$ 26,400								$ 35,100
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%
Year One										$ 14,100
Year Two										14,400
Year Three										$ 7,300
Debt Instrument, Interest Rate, Stated Percentage										2.30%	2.30%
Waterford Series Collateral Trust Mortgage Notes due 2017 [Member] | Entergy Louisiana [Member]
Debt Instrument [Line Items]
Implicit interest rate on notes issued											7.458%
Waterford 3 Lease Obligation [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage										0.00%	8.09%
Debt Instrument, Interest Rate, Stated Percentage										0.00%	8.09%
Waterford 3 Lease Obligation [Member] | Entergy Louisiana [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage											8.09%
Debt Instrument, Interest Rate, Stated Percentage											8.09%