Revolving Credit Facilities, Lines Of Credit And Short-Term Borrowings (Notes Payable By Variable Interest Entities) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012
Nine Percent Series H Notes Due June Two Thousand And Thirteen [Member] | Entergy Arkansas VIE [Member]
Notes payable by variable interest entities
Amount	$ 30
Five Point Six Nine Percent Series I Notes Due July Two Thousand Fourteen [Member] | Entergy Arkansas VIE [Member]
Notes payable by variable interest entities
Amount	70
Three Point Two Three Percent Series J Notes Due July Two Thousand Sixteen [Member] | Entergy Arkansas VIE [Member]
Notes payable by variable interest entities
Amount	55
Five Point Five Six Percent Series N Notes Due May Two Thousand Thirteen [Member] | Entergy Gulf States Louisiana VIE [Member]
Notes payable by variable interest entities
Amount	75
Five Point Four One Percent Series O Notes Due July Two Thousand Twelve [Member] | Entergy Gulf States Louisiana VIE [Member]
Notes payable by variable interest entities
Amount	60
Five Point Six Nine Percent Series E Notes Due July Two Thousand Fourteen [Member] | Entergy Louisiana VIE [Member]
Notes payable by variable interest entities
Amount	50
Three Point Three Percent Series F Note Due March Two Thousand Sixteen [Member] | Entergy Louisiana VIE [Member]
Notes payable by variable interest entities
Amount	20
Six Point Two Nine Percent Series F Notes Due September Two Thousand Thirteen [Member] | System Energy VIE [Member]
Notes payable by variable interest entities
Amount	70
Five Point Three Three Percent Series G Notes Due April Two Thousand Fifteen [Member] | System Energy VIE [Member]
Notes payable by variable interest entities
Amount	60
Four Point Zero Two Percent Series H Notes Due February Two Thousand Seventeen [Member] | System Energy VIE [Member]
Notes payable by variable interest entities
Amount	$ 50