Benefit Plans (Plan Assets And Benefit Obligations Recognized In Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Benefit Plans [Abstract]
Net loss	$ 21,208	$ 726
Prior service cost	338	13
Amortization of prior service cost	(707)	(643)
Amortization of actuarial loss	(1,525)	(1,098)	(858)
Total recognized in other comprehensive income or loss	19,314	(1,002)
Total recognized in net periodic pension expense and other comprehensive income or loss (before tax)	$ 26,946	$ 5,778