Retirement, Other Postretirement Benefits, And Defined Contribution Plans (One Percentage Point Change In Assumed Health Care Cost Trend Rate) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
1 Percentage Point Increase, Impact on the APBO	$ 274,059
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	28,455
1 Percentage Point Decrease, Impact on the APBO	(220,654)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(22,210)
Entergy Arkansas [Member]
1 Percentage Point Increase, Impact on the APBO	41,816
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	3,994
1 Percentage Point Decrease, Impact on the APBO	(33,880)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(3,138)
Entergy Gulf States Louisiana [Member]
1 Percentage Point Increase, Impact on the APBO	31,702
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	3,287
1 Percentage Point Decrease, Impact on the APBO	(25,554)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(2,568)
Entergy Louisiana [Member]
1 Percentage Point Increase, Impact on the APBO	30,780
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	3,237
1 Percentage Point Decrease, Impact on the APBO	(24,858)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(2,528)
Entergy Mississippi [Member]
1 Percentage Point Increase, Impact on the APBO	13,728
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	1,346
1 Percentage Point Decrease, Impact on the APBO	(11,139)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(1,057)
Entergy New Orleans [Member]
1 Percentage Point Increase, Impact on the APBO	8,410
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	779
1 Percentage Point Decrease, Impact on the APBO	(6,924)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(619)
Entergy Texas [Member]
1 Percentage Point Increase, Impact on the APBO	19,647
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	1,799
1 Percentage Point Decrease, Impact on the APBO	(16,034)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	(1,421)
System Energy [Member]
1 Percentage Point Increase, Impact on the APBO	11,304
1 Percentage Point Increase, Impact on the sum of service costs and interest cost	1,279
1 Percentage Point Decrease, Impact on the APBO	(9,027)
1 Percentage Point Decrease, Impact on the sum of service costs and interest cost	$ (994)