Summary Of Significant Accounting Policies (Effective AFUDC Rate) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010		Dec. 31, 2009
Summary Of Significant Accounting Policies [Abstract]
Effective AFUDC rate	7.91%	8.25%	[1]	8.22%

[1] Rate was effective from January 1, 2010 to November 30, 2010. Effective December 1, 2010, rate was changed to 7.91%.