Revolving Credit Facilities, Lines Of Credit And Short-Term Borrowings Revolving Credit Facilities, Lines Of Credit And Short-Term Borrowings (Uncommitted Standby Letter of Credit Facilities to Support MISO Obligations) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Entergy Texas [Member]
Letters of Credit Outstanding, Amount	$ 1.3
Credit Facility Of Twenty Five Million [Member] | Entergy Arkansas [Member]
Uncommitted Credit Facility	25
Letter of Credit Fee, Percentage	0.70%
Letters of Credit Outstanding, Amount	2.0
Credit Facility of Seventy Five Million [Member] | Entergy Gulf States [Member]
Uncommitted Credit Facility	75
Letter of Credit Fee, Percentage	0.70%
Letters of Credit Outstanding, Amount	26.0
Credit Facility of Fifty Million [Member] | Entergy Louisiana [Member]
Uncommitted Credit Facility	50
Letter of Credit Fee, Percentage	0.70%
Letters of Credit Outstanding, Amount	1.0
Credit Facility of Fifty Million [Member] | Entergy Texas [Member]
Uncommitted Credit Facility	50
Letter of Credit Fee, Percentage	0.70%
Letters of Credit Outstanding, Amount	11.0
Credit Facility of Forty Million [Member] | Entergy Mississippi [Member]
Uncommitted Credit Facility	40
Letters of Credit Outstanding, Amount	9.5
Credit Facility of Fifteen Million [Member] | Entergy New Orleans [Member]
Uncommitted Credit Facility	15
Letter of Credit Fee, Percentage	0.75%
Letters of Credit Outstanding, Amount	$ 8.5
Minimum [Member] | Credit Facility of Forty Million [Member] | Entergy Mississippi [Member]
Letter of Credit Fee, Percentage	0.70%
Maximum [Member] | Credit Facility of Forty Million [Member] | Entergy Mississippi [Member]
Letter of Credit Fee, Percentage	1.50%