Risk Management and Fair Values (Fair Values Of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
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	$ 8.0	[1]
Derivative liability as hedging instrument offset	(8)	[2]
Derivative Liability	0	[3],[4]
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	2.0	[1]	8.0	[1]
Derivative liability as hedging instrument offset	(2)	[2]	(8)	[2]
Derivative Liability	0	[3],[4]	0	[3],[4]
Other Deferred Debits And Other Assets [Member] | Electricity Swaps And Options [Member] | Entergy Wholesale Commodities [Member] | Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	39.0	[1]	48.0	[1]
Derivative asset as hedging instrument offset	(8)	[2]	0	[2]
Derivative Asset	31	[3],[4]	48	[3],[4]
Other Deferred Debits And Other Assets [Member] | Electricity Swaps And Options [Member] | Entergy Wholesale Commodities [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	2.0	[1]	9.0	[1]
Derivative asset as hedging instrument offset	(2)	[2]	(8)	[2]
Derivative Asset	0	[3],[4]	1	[3],[4]
Prepayments And Other [Member] | Electricity Swaps And Options [Member] | Entergy Wholesale Commodities [Member] | Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	118.0	[1]	149.0	[1]
Derivative asset as hedging instrument offset	(47)	[2]	(53)	[2]
Derivative Asset	71	[3],[4]	96	[3],[4]
Prepayments And Other [Member] | Electricity Swaps And Options [Member] | Entergy Wholesale Commodities [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	67.0	[1]	97.0	[1]
Derivative asset as hedging instrument offset	(10)	[2]	(25)	[2]
Derivative Asset	57	[3],[4]	72	[3],[4]
Prepayments And Other [Member] | Fixed Transmission Rights (FTRs) [Member] | Utility and Entergy Wholesale Commodities [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	15.0		50.0	[1]
Derivative asset as hedging instrument offset			(3)	[2]
Derivative Asset	15		47	[3],[4]
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	13.0	[1]	24.0	[1]
Derivative liability as hedging instrument offset	(13)	[2]	(24)	[2]
Derivative Liability	0	[3],[4]	0	[3],[4]
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	57.0	[1]	57.0	[1]
Derivative liability as hedging instrument offset	(43)	[2]	(55)	[2]
Derivative Liability	14.0	[3],[4]	2.0	[3],[4]
Other Current Liabilities [Member] | Natural Gas Swaps [Member] | Utility [Member] | Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	21.0	[1]	20.0	[1]
Derivative liability as hedging instrument offset	0	[1]	0	[2]
Derivative Liability	21.0	[3],[4]	20.0	[3],[4]
Entergy Gulf States Louisiana [Member] | Gas Hedge Contracts [Member] | Natural Gas Swaps [Member] | Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	7.8		8.2
Entergy Gulf States Louisiana [Member] | Prepayments And Other [Member] | Fixed Transmission Rights (FTRs) [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	5.0		14.4
Entergy Louisiana [Member] | Gas Hedge Contracts [Member] | Natural Gas Swaps [Member] | Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	9.7		7.6
Entergy Louisiana [Member] | Prepayments And Other [Member] | Fixed Transmission Rights (FTRs) [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	3.8		11.1
Entergy Mississippi [Member] | Prepayments And Other [Member] | Natural Gas Swaps [Member] | Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability	3.4		2.8
Entergy Mississippi [Member] | Prepayments And Other [Member] | Fixed Transmission Rights (FTRs) [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	0.9		3.4
Entergy New Orleans [Member] | Prepayments And Other [Member] | Natural Gas Swaps [Member] | Not Designated As Hedging Instrument [Member]
Liabilities:
Derivative Liability, Fair Value, Gross Liability			0.9
Entergy New Orleans [Member] | Prepayments And Other [Member] | Fixed Transmission Rights (FTRs) [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	1.4		4.1
Entergy Arkansas [Member] | Prepayments And Other [Member] | Fixed Transmission Rights (FTRs) [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	0.6		0.7
Entergy Texas [Member] | Prepayments And Other [Member] | Fixed Transmission Rights (FTRs) [Member] | Not Designated As Hedging Instrument [Member]
Assets:
Derivative Asset, Fair Value, Gross Asset	$ 3.4		$ 12.3

[1] Represents the gross amounts of recognized assets/liabilities

[2] Represents the netting of fair value balances with the same counterparty

[3] Excludes cash collateral in the amounts of $1 million posted as of March 31, 2015 and $25 million held as of December 31, 2014

[4] Represents the net amounts of assets /liabilities presented on the Entergy Consolidated Balance Sheets