Employee Benefit Plans (Net Periodic Benefit Cost (Benefit)) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Employee Benefit Plans [Abstract]
Expected return on plan assets, net of expenses	$ (11,434)	$ (11,008)	$ (9,126)
Interest cost on projected benefit obligation	7,892	7,724	7,973
Net amortization and deferral	3,130	2,915	4,231
Net periodic benefit cost (benefit)	$ (412)	$ (369)	$ 3,078