Rate And Regulatory Matters (2011 Rate Filing Based On Calendar Year 2010 Production Costs) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Oct. 31, 2011
Entergy Arkansas [Member]
Regulatory Assets [Line Items]
Payments (receipts) based on production costs	$ 41	$ 77	$ 156
Entergy Gulf States Louisiana [Member]
Regulatory Assets [Line Items]
Payments (receipts) based on production costs		(12)	(75)
Entergy Louisiana [Member]
Regulatory Assets [Line Items]
Payments (receipts) based on production costs	(41)
Entergy Mississippi [Member]
Regulatory Assets [Line Items]
Payments (receipts) based on production costs		(40)	(33)
Entergy New Orleans [Member]
Regulatory Assets [Line Items]
Payments (receipts) based on production costs	(17)	(25)	(5)
Entergy Texas [Member]
Regulatory Assets [Line Items]
Payments (receipts) based on production costs	$ 17		$ (43)