Rate and Regulatory Matters (Details Textual) (USD $)	1 Months Ended	12 Months Ended				1 Months Ended				3 Months Ended	12 Months Ended				1 Months Ended	12 Months Ended				1 Months Ended	3 Months Ended							12 Months Ended			39 Months Ended	1 Months Ended		12 Months Ended			1 Months Ended			12 Months Ended					12 Months Ended		3 Months Ended	12 Months Ended											12 Months Ended			12 Months Ended			3 Months Ended		12 Months Ended			12 Months Ended
	Mar. 31, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2005	Mar. 31, 2011 Entergy Gulf States Louisiana [Member]	Jan. 31, 2011 Entergy Gulf States Louisiana [Member]	Jun. 30, 2010 Entergy Gulf States Louisiana [Member]	Mar. 31, 2010 Entergy Gulf States Louisiana [Member]	Dec. 31, 2009 Entergy Gulf States Louisiana [Member]	Dec. 31, 2011 Entergy Gulf States Louisiana [Member]	Dec. 31, 2010 Entergy Gulf States Louisiana [Member]	Dec. 31, 2009 Entergy Gulf States Louisiana [Member]	Dec. 31, 2011 Entergy Gulf States Louisiana [Member] Gas [Member]	Mar. 31, 2010 Entergy Louisiana [Member]	Dec. 31, 2011 Entergy Louisiana [Member]	Dec. 31, 2010 Entergy Louisiana [Member]	Dec. 31, 2009 Entergy Louisiana [Member]	Dec. 31, 2008 Entergy Louisiana [Member]	Nov. 30, 2011 Entergy Texas [Member]	Dec. 31, 2011 Entergy Texas [Member]	Dec. 31, 2010 Entergy Texas [Member]	Sep. 30, 2010 Entergy Texas [Member]	Jun. 30, 2010 Entergy Texas [Member]	Mar. 31, 2010 Entergy Texas [Member]	Dec. 31, 2009 Entergy Texas [Member]	Jun. 30, 2009 Entergy Texas [Member]	Dec. 31, 2011 Entergy Texas [Member]	Dec. 31, 2010 Entergy Texas [Member]	Dec. 31, 2009 Entergy Texas [Member]	Jun. 30, 2010 Entergy Texas [Member]	Jun. 30, 2010 Entergy Mississippi [Member]	Mar. 31, 2010 Entergy Mississippi [Member]	Dec. 31, 2011 Entergy Mississippi [Member]	Dec. 31, 2010 Entergy Mississippi [Member]	Dec. 31, 2009 Entergy Mississippi [Member]	May 31, 2011 Entergy Louisiana, LLC [Member]	Jun. 30, 2010 Entergy New Orleans [Member]	Mar. 31, 2007 Entergy New Orleans [Member]	Dec. 31, 2011 Entergy New Orleans [Member]	Dec. 31, 2010 Entergy New Orleans [Member]	Dec. 31, 2009 Entergy New Orleans [Member]	Dec. 31, 2007 Entergy New Orleans [Member]	Apr. 02, 2009 Entergy New Orleans [Member]	Dec. 31, 2011 Entergy New Orleans [Member] Electric [Member]	Dec. 31, 2011 Entergy New Orleans [Member] Gas [Member]	Jun. 30, 2010 Entergy Arkansas [Member]	Dec. 31, 2011 Entergy Arkansas [Member]	Dec. 31, 2010 Entergy Arkansas [Member]	Dec. 31, 2009 Entergy Arkansas [Member]	Dec. 31, 2007 Entergy Arkansas [Member]	Dec. 31, 2011 System Energy [Member]	Dec. 31, 2010 System Energy [Member]	Dec. 31, 2009 System Energy [Member]	Dec. 31, 2005 System Energy [Member]	Dec. 31, 2010 Hurricane Gustav and Hurricane Ike [Member] Entergy Gulf States Louisiana [Member] Y	Dec. 31, 2009 Hurricane Gustav and Hurricane Ike [Member] Entergy Gulf States Louisiana [Member]	Jul. 31, 2010 Hurricane Gustav and Hurricane Ike [Member] Entergy Gulf States Louisiana [Member]	Dec. 31, 2010 Hurricane Gustav and Hurricane Ike [Member] Entergy Louisiana [Member] Y	Dec. 31, 2009 Hurricane Gustav and Hurricane Ike [Member] Entergy Louisiana [Member]	Jul. 31, 2010 Hurricane Gustav and Hurricane Ike [Member] Entergy Louisiana [Member]	Dec. 31, 2011 Hurricane Gustav and Hurricane Ike [Member] Entergy Texas [Member]	Dec. 31, 2009 Hurricane Gustav and Hurricane Ike [Member] Entergy Texas [Member]	Aug. 05, 2009 Hurricane Gustav and Hurricane Ike [Member] Entergy Texas [Member]	Jun. 30, 2009 Hurricane Gustav and Hurricane Ike [Member] Operation and Maintenance Expense [Member] Entergy Texas [Member]	Jun. 30, 2009 Hurricane Gustav and Hurricane Ike [Member] Utility [Member] Entergy Texas [Member]	Dec. 31, 2008 Hurricane Katrina and Hurricane Rita [Member] Entergy Gulf States Louisiana [Member] Y	Dec. 31, 2011 Hurricane Katrina and Hurricane Rita [Member] Entergy Gulf States Louisiana [Member]	Aug. 26, 2008 Hurricane Katrina and Hurricane Rita [Member] Entergy Gulf States Louisiana [Member]	Dec. 31, 2008 Hurricane Katrina and Hurricane Rita [Member] Entergy Louisiana [Member] Y	Dec. 31, 2011 Hurricane Katrina and Hurricane Rita [Member] Entergy Louisiana [Member]	Jul. 29, 2008 Hurricane Katrina and Hurricane Rita [Member] Entergy Louisiana [Member]
Rate and Regulatory Matters (Textual) [Abstract]
Purchase power and capacity cost											$ 100,100,000	$ 100,100,000				$ 68,000,000	$ 68,000,000																							$ 4,100,000	$ 4,100,000
Time period of expected recovery of cost		Over a period greater than twelve months
Minimum period of expected recovery of fuel power capacity cost		12 months
Time taken to file the analysis		Within 60 days of the order
Realignment to base rates of SO2 costs											2,000,000
Refund to customers including interest											18,000,000
Request filed for refund of fuel cost recovery over-collections																								66,000,000		71,000,000	46,100,000	43,000,000
Request filed for refund of fuel cost recovery over-collections including interest																					67,000,000
Refund for fuel cost recovery																100,000						73,000,000	77,000,000		87,800,000		59,200,000	0
Reconciliation of fuel and purchased power cost																												1,300,000,000		1,800,000,000
Additional allocation for decision recommendation																											18,600,000
Charge to Earnings																											13,000,000
Earned return on common equity							8.84%																							11.50%							11.07%
Earned return on common equity						11.76%					11.11%			11.76%						10.60%
Revenue deficiency							300,000
Base rate recovery adjustment from fuel adjustment clause recovery to base rate recovery																12,500,000
Trapped costs at Entergy Arkansas																																																			14,500,000
Decrease in electric base revenue																																									18,000,000
Rate Increase requested in Texas rate case																														198,700,000
Increase In Base Rate Reflecting Return On Common Equity																				112,000,000
Increase in gas base rate																																								0
Increase in electric base rate, percentage as per settlement																																											0.00%
Amortization of rate case costs																							11,000,000
Total annual production costs - limit					Each company's total annual production costs will have to be within +/-11% of Entergy System average total annual production costs
Payments from utility operating companies as percentage of average production cost																																																							11.00%
Net reduction for decreased capacity costs and base rate reclassification																		13,800,000
Prospective bandwidth remedy, start date		Jun. 01, 2005
River Bend annual Decommissioning costs per settlement																													2,000,000
Bandwidth payment to be received																																																			14,500,000
Amount collected from customers																																																156,000,000
Period for collection																																																22 months
Provisions for rate refund including interest																			16,000,000
Damages caused by the non-requirements sales																																																		144,000,000
Financing order authorized to issue storm cost recovery bonds																																																	126,300,000													566,400,000
Up front financing costs including in storm cost recovery bonds																																																	4,600,000
Carrying costs including in storm cost recovery bonds																																																	11,500,000
Unrecoverable storm cost charged to earning																																																									4,400,000			7,200,000
Total recoverable costs																																																									234,000,000			394,000,000
Replenishment amount for storm reserve spending																																																									90,000,000			200,000,000
Amount of disallowed fuel costs for the period April 2007 through June 2009 per settlement with the PUCT																															3,250,000
Minimum amount of benefits committed to pass on to the customers																																																									15,500,000			27,750,000								10,000,000			30,000,000
Share of River Bend																														70.00%
Prospective Annual rate reductions for five years																																																									3,100,000			5,550,000								2,000,000			6,000,000
Bond issued by LCDA																																																										244,100,000			468,900,000								278,400,000			687,700,000
Proceed from loan by LCDA to corporation LURC																																																								240,300,000			462,400,000								274,700,000			679,000,000
Amount transfer to restricted escrow account as storm damage reserve by LURC																																																								90,000,000			200,000,000								87,000,000			152,000,000
Revenue requirement to provide supplemental funding																														2,800,000
Amount Transferred to Entergy Louisiana																																																								150,300,000			262,400,000								187,700,000			527,000,000
Amount used to acquire membership interest units in Entergy Holdings Company LLC																																																								150,300,000			262,400,000								189,400,000			545,000,000
Class preferred, non-voting, membership interest units																																																								1,502,643.04			2,624,297.11								1,893,918.39			5,449,861.85
Annual distribution rate																																																								9.00%			9.00%								10.00%			10.00%
Liquidation price per unit																																																								100			100								100			100
Additional Increase in Texas base rates for bills rendered beginning May 2, 2011																												9,000,000
Maturity period																																																								10			10								10			10
Net worth required under terms of membership interest																																																								1,000,000,000			1,000,000,000								1,000,000,000			1,000,000,000
Amount withdrawn from restricted escrow account as approved by units of wholly owned subsidiary																																																																			1,700,000			17,800,000
Storm related costs																																							205,000,000
Amount received for CDBG funds																																									19,200,000		180,800,000
Recoverable costs including estimated costs for works to be completed																																																																577,500,000
Total recoverable costs																																																															566,400,000
Stipulation agreement not to recover storm restoration spending																																																															11,100,000			4,300,000
Operation and maintenance expense		2,867,758,000	2,969,402,000	2,750,810,000							351,070,000	361,329,000	332,450,000			470,783,000	432,341,000	401,898,000										214,191,000	209,699,000	204,524,000				210,657,000	217,354,000	217,452,000				106,817,000	130,917,000	108,716,000						511,592,000	495,443,000	475,222,000		136,495,000	124,690,000	120,707,000											6,800,000
Settlement and subsequent compliance tariffs																																															63,700,000
Return on common equity provided by settlement																																															10.20%
Increase in Texas base rates for electricity usage beginning August 15,2010																													59,000,000
Entergy Louisiana reset return rates													10.65%					10.25%
Under the formula rate plan ,over and under earnings outside an allowed range are allocated to customers in percent											60.00%					60.00%
Under the formula rate plan ,over and under earnings outside an allowed range are allocated to subsidiary in percent											40.00%					40.00%
Basis point band width										Plus or minus 75 basis point bandwidth			10.5% plus or minus fifty basis points		Plus or minus 80 basis point bandwidth
Basis point band width											10.5%, plus or minus fifty basis points
Entergy Louisiana rate reset increase													44,300,000					2,500,000
Cost of service adjustment													36,900,000					16,300,000
Net increased capacity costs and base rate reclassification													7,400,000
Additional rate increase pursuant to a special rate implementation									23,900,000
Recommended reduction in return on current rates by LPSC staff								800,000									100,000
Recommended reduction in return on current rates by LPSC staff						200,000
Percentage of return on equity											10.48%					11.05%
Energy settlement refund to customers including interest								500,000
Percentage of LPSC regulated share of River Bend												70.00%
Return on common equity on formula rate plan												10.25%					10.82%																												11.10%	10.75%
Increase in the revenue requirement for decommissioning												7,800,000					3,500,000
Increase in Incremental Capacity costs												25,200,000					2,200,000
Rate Increase Value For Incremental Capacity Costs																9,000
Eliminating the 50/50 sharing that had been in the plan																																	50/50
Current rate change limit of two percent of revenues																																	2.00%
Revenue adjustment cap																																	14,500,000
Proposed rate change limit of four percent of revenues																																	4.00%
Deferral as regulatory asset of legal expenses																																3,900,000
Reduction in combined fuel and non-fuel electric revenue requirement																																												35,300,000
Conversion of voluntary recovery credit to a permanent reduction and substantial realignment of cost recovery																																												10,600,000
Basis point bandwidth																																													Plus or minus 40 basis point bandwidth	Plus or minus 50 basis point bandwidth
Amount authorized for storm reserve																																											75,000,000
Request for electric base revenue decrease																																						12,800,000
Request for gas base revenue increase																																						2,400,000
Amount included in electric rates per year to fund the smart energy efficiency programs as per rate case settlement																																										3,100,000
Interim rate increase subject to refund																													17,500,000
Increase in base rate due to settlement				4,950,000
Increase in interim rate maximum due to testimony results				58,000,000
Development cost associated with nuclear generation																																			49,000,000
Cost incurred in connection with planning, evaluation and monitoring																																		57,000,000
Effective date of special formula rate plan rate implementation filing with LPSC											May 11, 2012					May 11, 2012
Rate decrease reflects special formula rate plan rate implementation filing with LPSC											5,100,000	22,800,000				1,100,000
Rate Increase reflects special formula rate plan rate implementation filing with LPSC																43,100,000
Entergy Louisiana rate reset decrease	200,000
Electric rate decrease																																								6,500,000
Gas rate decrease																																								1,100,000
Incremental electric rate decrease																																								8,500,000
Incremental gas rate decrease																																								1,600,000
Deferral plant maintenance expenses																																								13,400,000
Regulatory Liabilities											$ (30,300,000)	$ (24,900,000)				$ (62,600,000)	$ (52,900,000)