Risk Management and Fair Values (Fair Values Of Derivative Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Utility [Member]
Liabilities:
Letters of Credit Outstanding, Amount	$ 5,000
Entergy Wholesale Commodities [Member]
Derivatives, Fair Value [Line Items]
Cash collateral posted	30,000	$ 1,000
Assets:
Derivative, Collateral, Obligation to Return Cash		4,000
Liabilities:
Letters of Credit Held		34,000
Other Non-Current Liabilities [Member] \| Electricity Swaps And Options [Member] \| Entergy Wholesale Commodities [Member] \| Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	24,000	17,000
Derivative, Collateral, Right to Reclaim Cash	11,000	14,000
Derivative Liability	13,000	3,000
Other Non-Current Liabilities [Member] \| Electricity Swaps And Options [Member] \| Entergy Wholesale Commodities [Member] \| Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	1,000
Derivative, Collateral, Right to Reclaim Cash	0
Derivative Liability	1,000
Other Deferred Debits And Other Assets [Member] \| Electricity Swaps And Options [Member] \| Entergy Wholesale Commodities [Member] \| Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	0	5,000
Derivative Asset, Fair Value, Gross Asset	10,000	19,000
Derivative, Collateral, Obligation to Return Cash	10,000	14,000
Prepayments And Other [Member] \| Electricity Swaps And Options [Member] \| Entergy Wholesale Commodities [Member] \| Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	0	0
Derivative Asset, Fair Value, Gross Asset	10,000	19,000
Derivative, Collateral, Obligation to Return Cash	10,000	19,000
Prepayments And Other [Member] \| Electricity Swaps And Options [Member] \| Entergy Wholesale Commodities [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	0	0
Derivative Asset, Fair Value, Gross Asset	3,000	9,000
Derivative, Collateral, Obligation to Return Cash	3,000	9,000
Prepayments And Other [Member] \| Natural Gas Swaps [Member] \| Utility [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	1,000
Derivative Asset, Fair Value, Gross Asset	1,000
Prepayments And Other [Member] \| Fixed Transmission Rights (FTRs) [Member] \| Utility and Entergy Wholesale Commodities [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	29,000	21,000
Derivative Asset, Fair Value, Gross Asset	31,000	22,000
Derivative, Collateral, Obligation to Return Cash	2,000	1,000
Other Current Liabilities [Member] \| Electricity Swaps And Options [Member] \| Entergy Wholesale Commodities [Member] \| Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	62,000	86,000
Derivative, Collateral, Right to Reclaim Cash	10,000	20,000
Derivative Liability	52,000	66,000
Other Current Liabilities [Member] \| Electricity Swaps And Options [Member] \| Entergy Wholesale Commodities [Member] \| Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	4,000	9,000
Derivative, Collateral, Right to Reclaim Cash	3,000	8,000
Derivative Liability	1,000	1,000
Other Current Liabilities [Member] \| Natural Gas Swaps [Member] \| Utility [Member] \| Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability		6,000
Derivative, Collateral, Right to Reclaim Cash		0
Derivative Liability		6,000
Entergy Louisiana [Member] \| Prepayments And Other [Member] \| Natural Gas Swaps [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	1,000
Derivative Asset, Fair Value, Gross Asset	1,000
Derivative, Collateral, Obligation to Return Cash	0
Entergy Louisiana [Member] \| Prepayments And Other [Member] \| Fixed Transmission Rights (FTRs) [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	12,000	10,200
Derivative Asset, Fair Value, Gross Asset	12,200	11,000
Derivative, Collateral, Obligation to Return Cash	(200)	(800)
Entergy Louisiana [Member] \| Other Current Liabilities [Member] \| Natural Gas Swaps [Member] \| Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability		5,000
Derivative, Collateral, Right to Reclaim Cash		0
Derivative Liability		5,000
Entergy Mississippi [Member]
Liabilities:
Letters of Credit Outstanding, Amount	200	100
Entergy Mississippi [Member] \| Prepayments And Other [Member] \| Natural Gas Swaps [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	400
Derivative Asset, Fair Value, Gross Asset	400
Derivative, Collateral, Obligation to Return Cash	0
Entergy Mississippi [Member] \| Prepayments And Other [Member] \| Fixed Transmission Rights (FTRs) [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	3,700	2,100
Derivative Asset, Fair Value, Gross Asset	3,700	2,100
Derivative, Collateral, Obligation to Return Cash	0	0
Entergy Mississippi [Member] \| Other Current Liabilities [Member] \| Natural Gas Swaps [Member] \| Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability		1,200
Derivative, Collateral, Right to Reclaim Cash		0
Derivative Liability		1,200
Entergy New Orleans [Member] \| Prepayments And Other [Member] \| Fixed Transmission Rights (FTRs) [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	2,100	2,200
Derivative Asset, Fair Value, Gross Asset	2,100	2,200
Derivative, Collateral, Obligation to Return Cash	0	0
Entergy New Orleans [Member] \| Other Current Liabilities [Member] \| Natural Gas Swaps [Member] \| Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability		200
Derivative, Collateral, Right to Reclaim Cash		0
Derivative Liability		200
Entergy Arkansas [Member]
Liabilities:
Letters of Credit Outstanding, Amount	1,000	200
Entergy Arkansas [Member] \| Prepayments And Other [Member] \| Fixed Transmission Rights (FTRs) [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	11,300	3,000
Derivative Asset, Fair Value, Gross Asset	11,600	3,200
Derivative, Collateral, Obligation to Return Cash	(300)	(200)
Entergy Texas [Member]
Liabilities:
Letters of Credit Outstanding, Amount	3,600	50
Entergy Texas [Member] \| Prepayments And Other [Member] \| Fixed Transmission Rights (FTRs) [Member] \| Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset	100	3,400
Derivative Asset, Fair Value, Gross Asset	1,700	3,600
Derivative, Collateral, Obligation to Return Cash	$ (1,600)	$ (200)

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