Summary Of Significant Accounting Policies (Narrative) (Details) $ in Thousands		1 Months Ended		3 Months Ended				12 Months Ended
		Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Dec. 31, 2015 USD ($) $ / MWh $ / kWh plant shares	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013 USD ($) shares	Sep. 01, 2015 USD ($)
Depreciation rates on average depreciable property								2.90%	2.80%	2.60%
Depreciation rates on average depreciable utility property								2.70%	2.50%	2.50%
Depreciation rates on average depreciable non-utility property								5.40%	5.50%	4.10%
Accumulated depreciation of non-utility property		$ 185,500		$ 163,800				$ 163,800	$ 185,500
Construction expenditures in accounts payable		209,000		234,000				$ 234,000	$ 209,000
Options outstanding excluded from the calculation of diluted earnings per share | shares								7,399,820	5,743,013	8,866,542
Stock-based compensation plans award vesting period								3 years
Portion of percentage of interest of River Bend plant costs, generation, revenues and expenses operating the Louisiana retail deregulated portion of River Bend								15.00%
Limit above which incremental revenue shared between ratepayers and shareholders | $ / kWh								0.046
Asset Retirement Obligations, Noncurrent		4,458,296		4,790,187				$ 4,790,187	$ 4,458,296
Asset Write-Offs, Impairments, And Related Charges								2,104,906	123,527	$ 341,537
Property, Plant and Equipment, Net		213,791		219,999				219,999	213,791
Present Value Of The Difference Between The Stipulated Contract Amount For Decommissioning The Plants Less The Decommissioning Cost				420,800				420,800
Asset Write-Offs, Impairments, And Related Charges								2,104,906	179,752	341,537
Decommissioning								$ 280,272	$ 272,621	$ 242,104
Entergy Louisiana [Member]
Purchase price of net assets that support Algiers customers											$ 85,000
Depreciation rates on average depreciable property								2.30%	2.20%	2.20%
Accumulated depreciation of non-utility property		154,200		150,100				$ 150,100	$ 154,200
Construction expenditures in accounts payable		71,400		68,600				$ 68,600	71,400
Percentage Interest in River Bend								30.00%
Rate at which electricity sold to retail customers | $ / kWh								0.046
Asset Retirement Obligations, Noncurrent		950,353		1,027,862				$ 1,027,862	950,353
Property, Plant and Equipment, Net		193,621		206,293				206,293	193,621
Asset Write-Offs, Impairments, And Related Charges		16,000
Decommissioning								$ 43,445	$ 41,493	$ 37,520
Entergy Texas [Member]
Depreciation rates on average depreciable property								2.60%	2.50%	2.50%
Accumulated depreciation of non-utility property		10,400		4,900				$ 4,900	$ 10,400
Construction expenditures in accounts payable		24,100		33,100				33,100	24,100
Asset Retirement Obligations, Noncurrent		4,610		6,124				6,124	4,610
After tax asset impairment charge								15,300
Property, Plant and Equipment, Net		376		376				376	376
Asset Write-Offs, Impairments, And Related Charges								$ 23,472	$ 0	$ 0
Entergy Arkansas [Member]
Depreciation rates on average depreciable property								2.60%	2.40%	2.50%
Construction expenditures in accounts payable		37,300		43,000				$ 43,000	$ 37,300
Asset Retirement Obligations, Noncurrent		818,351		872,346				872,346	818,351
Decommissioning								$ 50,414	$ 46,972	$ 43,058
Parent Company [Member]
Incremental Common Shares Attributable to Share-based Payment Arrangements | shares								0	300,000	100,000
Entergy Mississippi [Member]
Depreciation rates on average depreciable property								3.20%	2.60%	2.60%
Accumulated depreciation of non-utility property		2,200		500				$ 500	$ 2,200
Construction expenditures in accounts payable		7,800		11,400				11,400	7,800
Asset Retirement Obligations, Noncurrent		6,786		8,252				8,252	6,786
Property, Plant and Equipment, Net		4,642		4,625				$ 4,625	$ 4,642
Entergy New Orleans [Member]
Purchase price of net assets that support Algiers customers					$ 85,000
Cash Paid to Entergy Louisiana for Algiers Assets			$ 59,600
Depreciation rates on average depreciable property								3.00%	3.20%	3.30%
Construction expenditures in accounts payable		900		1,500				$ 1,500	$ 900
Asset Retirement Obligations, Noncurrent		2,511		2,687				2,687	2,511
Property, Plant and Equipment, Net		1,016		1,016				1,016	$ 1,016
Payable due Entergy Louisiana				25,500				$ 25,500			$ 25,500
System Energy [Member]
Depreciation rates on average depreciable property								2.80%	3.00%	2.80%
Construction expenditures in accounts payable		7,700		6,800				$ 6,800	$ 7,700
Asset Retirement Obligations, Noncurrent		$ 757,918		803,405				803,405	757,918
Decommissioning								$ 47,993	41,835	$ 35,472
Entergy Wholesale Commodities [Member]
Number of nuclear power plants pending for NRC license renewals | plant								2
Number of Remaining Operating Nuclear Power Generating Facilities								2
Severance and Employee Retention Costs								$ 8,000	46,000
Asset Write-Offs, Impairments, And Related Charges	[1]							2,036,234	$ 107,527	329,336
Projected Severance and Employee Retention Costs for 2016-2019				175,000				175,000
Vermont Yankee [Member]
Asset Impairment Charges						$ 113,000
After tax asset impairment charge						74,000
Vermont Yankee [Member] | Entergy Wholesale Commodities [Member]
Increase in decommissioning liability			$ 101,600			$ 101,600	$ 58,000			$ 27,200
Carrying value of nuclear plant							349,000
Asset Write-Offs, Impairments, And Related Charges							291,500
Impairment of Long-Lived Assets Held-For-Use, Net of Tax							183,700
Assets, Fair Value Disclosure							$ 62,000
FitzPatrick [Member] | Entergy Wholesale Commodities [Member]
Carrying value of nuclear plant					742,000
Asset Impairment Charges					48,000
After tax asset impairment charge					624,000
Asset Write-Offs, Impairments, And Related Charges					713,000
Assets, Fair Value Disclosure					29,000
Present Value Of The Difference Between The Stipulated Contract Amount For Decommissioning The Plants Less The Decommissioning Cost					335,000
Present Value Of The Difference Between The Stipulated Contract Amount For Decommissioning The Plants Less The Decommissioning Cost After Impairment					131,000
Change in Contract Amount For Decommissioning The Plants Less The Decommissioning Cost					204,000
Asset Write-Offs, Impairments, And Related Charges					965,000
Pilgrim [Member] | Entergy Wholesale Commodities [Member]
Carrying value of nuclear plant					718,000
Asset Impairment Charges					24,000
After tax asset impairment charge					438,000
Asset Write-Offs, Impairments, And Related Charges					653,000
Assets, Fair Value Disclosure					65,000
Asset Write-Offs, Impairments, And Related Charges					677,000
Decommissioning					134,000
Palisades [Member] | Entergy Wholesale Commodities [Member]
Increase in decommissioning liability				42,000				42,000
Carrying value of nuclear plant				859,000				859,000
Asset Write-Offs, Impairments, And Related Charges				396,000
Impairment of Long-Lived Assets Held-For-Use, Net of Tax				256,000
Assets, Fair Value Disclosure				463,000				463,000
Fitzpatrick And Pilgrim [Member] | Entergy Wholesale Commodities [Member]
Asset Write-Offs, Impairments, And Related Charges					1,642,000
Impairment of Long-Lived Assets Held-For-Use, Net of Tax					$ 1,062,000
Indian Point [Member] | Entergy Wholesale Commodities [Member]
Carrying value of nuclear plant				$ 2,360,000				$ 2,360,000
Maximum [Member] | Palisades [Member]
Power Purchase Agreement Price Escalated Annually | $ / MWh								61.50

[1] Businesses marked with * are sometimes referred to as the “competitive businesses.” Eliminations are primarily intersegment activity. Almost all of Entergy’s goodwill is related to the Utility segment.