Acquisitions and Dispositions Acquisitions and Dispositions (Narrative) (Details)	1 Months Ended		3 Months Ended				9 Months Ended		12 Months Ended
	Mar. 31, 2017 USD ($) MW	Aug. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) $ / MWh	Sep. 30, 2016 USD ($)	Dec. 31, 2022 $ / MWh	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2007 $ / MWh
Payments to Acquire Property, Plant, and Equipment							$ 0	$ (949,329,000)
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property				$ 0		$ 0	(16,270,000)	0
Fitzpatrick [Member]
Capacity Of Power Plant Unit | MW	838
Proceeds from Divestiture of Businesses	$ 110,000,000
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property	(16,000,000)
Cost of Reimbursable Expense	8,000,000
Non-refundable signing fee paid upon agreement and assumption by Exelon of certain liabilities		$ 10,000,000
Income tax benefit resulting from sale of FitzPatrick					$ 44,000,000
Decommissioning Fund Investments, Fair Value	805,000,000				805,000,000
Asset Retirement Obligation	727,000,000				727,000,000
Other operation and maintenance expense reimbursement					98,000,000
Reimbursement Revenue					7,000,000
Reimbursement for taxes other than income taxes					3,000,000
Nuclear defueling credit					10,000,000
Net Book Value	$ 0				$ 0
Entergy Arkansas [Member]
Payments to Acquire Property, Plant, and Equipment							0	(237,324,000)
Entergy Louisiana [Member]
Payments to Acquire Property, Plant, and Equipment							0	(474,670,000)
Entergy New Orleans [Member]
Payments to Acquire Property, Plant, and Equipment							$ 0	$ (237,335,000)
Entergy Wholesale Commodities [Member] | Palisades [Member]
Percentage Of Plants Output Covered By Purchased Power Agreement														100.00%
Price Under PPA Lower Range Per MWH | $ / MWh														43.50
Average Price Under PPA | $ / MWh							51
Scenario, Forecast [Member] | Entergy Wholesale Commodities [Member] | Palisades [Member]
Price Under PPA Upper Range Per MWH | $ / MWh									61.50
Subsequent Event [Member] | Entergy Wholesale Commodities [Member] | Palisades [Member]
Accelerated Finite Lived Intangible Assets Amortization Expenses due to termination of PPA			$ 2,000,000							$ 12,000,000	$ 11,000,000	$ 10,000,000	$ 6,000,000