Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net periodic benefit cost for both the Executive Retirement Plan and the Outside Director Plan
Service costs	$ 69	$ 51	$ 286
Interest costs	856	933	926
Effect of settlement		(243)	1,005
Amortization of net gain/loss	929	671	669
Total	1,854	1,412	2,886
Net loss (gain) recognized in other comprehensive income	(1,936)	676	(1,868)
Total recognized in net periodic benefit cost and accumulated other comprehensive loss	$ (82)	$ 2,088	$ 1,018