Variable Interest Entities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Entergy Louisiana [Member]
Variable Interest Entities (Textual) [Abstract]
Payments on lease, including interest	$ 12.3	$ 12.8	$ 39.1	$ 50.4
System Energy [Member]
Variable Interest Entities (Textual) [Abstract]
Payments on lease, including interest	$ 1.8	$ 2.0	$ 50.0	$ 49.4
Waterford Three [Member]
Variable Interest Entities (Textual) [Abstract]
Percentage in power plant owned by VIE			9.30%
Grand Gulf [Member]
Variable Interest Entities (Textual) [Abstract]
Percentage in power plant owned by VIE			11.50%