Summary Of Significant Accounting Policies (Schedule Of Net Property, Plant, And Equipment) (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	$ 3,654,000,000	$ 3,344,000,000
Distribution	6,561,000,000	6,157,000,000
Other	1,654,000,000	1,716,000,000
Construction work in progress	1,365,699,000	1,779,723,000
Nuclear fuel	1,598,000,000	1,546,000,000
Property, plant and equipment - net	27,298,545,000	25,609,285,000
Entergy Arkansas [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	1,034,000,000	942,000,000
Distribution	1,747,000,000	1,700,000,000
Other	115,000,000	173,000,000
Construction work in progress	205,982,000	120,211,000
Nuclear fuel	304,000,000	273,000,000
Property, plant and equipment - net	5,099,738,000	4,640,174,000
Entergy Gulf States Louisiana [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	573,000,000	500,000,000
Distribution	939,000,000	856,000,000
Other	187,000,000	192,000,000
Construction work in progress	125,448,000	122,051,000
Nuclear fuel	147,000,000	206,000,000
Property, plant and equipment - net	3,684,507,000	3,620,336,000
Entergy Louisiana [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	734,000,000	706,000,000
Distribution	1,454,000,000	1,304,000,000
Other	289,000,000	278,000,000
Construction work in progress	404,714,000	559,437,000
Nuclear fuel	204,000,000	165,000,000
Property, plant and equipment - net	5,946,346,000	5,251,581,000
Entergy Mississippi [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	581,000,000	510,000,000
Distribution	1,065,000,000	1,009,000,000
Other	201,000,000	206,000,000
Construction work in progress	62,876,000	105,083,000
Property, plant and equipment - net	2,455,104,000	2,179,743,000
Entergy New Orleans [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	27,000,000	22,000,000
Distribution	331,000,000	298,000,000
Other	182,000,000	186,000,000
Construction work in progress	11,135,000	13,610,000
Property, plant and equipment - net	539,675,000	513,478,000
Entergy Texas [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	642,000,000	624,000,000
Distribution	1,025,000,000	990,000,000
Other	106,000,000	110,000,000
Construction work in progress	90,469,000	90,856,000
Property, plant and equipment - net	2,233,896,000	2,140,298,000
System Energy [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	28,000,000	5,000,000
Other	17,000,000	18,000,000
Construction work in progress	40,392,000	357,826,000
Nuclear fuel	253,000,000	158,000,000
Property, plant and equipment - net	2,281,239,000	1,927,050,000
Utility Plants [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	3,619,000,000	3,309,000,000
Distribution	6,561,000,000	6,157,000,000
Other	1,416,000,000	1,463,000,000
Nuclear fuel	907,000,000	802,000,000
Entergy Wholesale Commodities [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Transmission	35,000,000	35,000,000
Other	235,000,000	250,000,000
Nuclear fuel	691,000,000	744,000,000
Parent & Other [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Other	3,000,000	3,000,000
Nuclear Plant [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	9,588,000,000	8,635,000,000
Nuclear Plant [Member] | Entergy Arkansas [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	1,073,000,000	1,034,000,000
Nuclear Plant [Member] | Entergy Gulf States Louisiana [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	1,428,000,000	1,458,000,000
Nuclear Plant [Member] | Entergy Louisiana [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	2,180,000,000	1,561,000,000
Nuclear Plant [Member] | System Energy [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	1,943,000,000	1,388,000,000
Nuclear Plant [Member] | Utility Plants [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	6,624,000,000	5,441,000,000
Nuclear Plant [Member] | Entergy Wholesale Commodities [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	2,964,000,000	3,194,000,000
Other Plant In Service [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	2,878,000,000	2,431,000,000
Other Plant In Service [Member] | Entergy Arkansas [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	621,000,000	398,000,000
Other Plant In Service [Member] | Entergy Gulf States Louisiana [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	286,000,000	286,000,000
Other Plant In Service [Member] | Entergy Louisiana [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	680,000,000	679,000,000
Other Plant In Service [Member] | Entergy Mississippi [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	545,000,000	350,000,000
Other Plant In Service [Member] | Entergy New Orleans [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	(11,000,000)	(7,000,000)
Other Plant In Service [Member] | Entergy Texas [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	371,000,000	325,000,000
Other Plant In Service [Member] | Utility Plants [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	2,493,000,000	2,032,000,000
Other Plant In Service [Member] | Entergy Wholesale Commodities [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Production	$ 385,000,000	$ 399,000,000