Defined Benefit Pension Plans Schedule of Net Periodic Pension Benefit Costs (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Schedule of Net Periodic Pension Benefit Costs [Line Items]
Service Cost	$ 637	$ 493	$ 1,855	$ 1,493
Interest Cost	947	858	2,833	2,608
Expected Return on Plan Assets	(80)	(73)	(243)	(221)
Amortization of Actuarial Net Loss (Gains)	14	(6)	42	(19)
Amortization of Unrecognized Prior Service Costs	18	0	55	0
Net Periodic Benefit Cost	$ 1,536	$ 1,272	$ 4,542	$ 3,861