Summary Of Significant Accounting Policies (Other Expense-Net) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Summary Of Significant Accounting Policies [Abstract]
Interest income	$ (455)	$ (393)	$ (1,029)	$ (991)
Interest on regulatory deferrals	(15)	(58)	(83)	(188)
Equity-related AFUDC	(421)	(552)	(1,655)	(1,436)
Net loss on investments	560	137	597	766
Other expense	1,957	1,676	5,466	5,718
Other income		(3)	(235)	(394)
Total	$ 1,626	$ 807	$ 3,061	$ 3,475