Rate And Regulatory Matters (Payments or Receipts Among Utility Operating Companies Production Cost Based) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	May 31, 2014
Entergy Arkansas [Member]
Payments (receipts) based on production costs	$ 38
Entergy Gulf States Louisiana [Member]
Payments (receipts) based on production costs	(22)	0
Entergy Louisiana [Member]
Payments (receipts) based on production costs	(16)	0
Entergy Mississippi [Member]
Payments (receipts) based on production costs	16	0
Entergy New Orleans [Member]
Payments (receipts) based on production costs	(1)	(15)
Entergy Texas [Member]
Payments (receipts) based on production costs	$ (15)	$ 15