Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net Income	$ 21,933	$ 21,892	$ 21,792
Other Comprehensive Income (Loss), Net of Tax:
Unrealized Securities Holding Gains Arising During the Period	4,741	1,514	707
Reclassification Adjustment for Net Securities Gains Included in Net Income, Net of Tax	(1,688)	(910)	(215)
Reclassification Adjustment for Other-Than-Temporary Impairment	0	0	226
Net Retirement Plan (Loss) Gain	(3,701)	(1,093)	1,483
Net Retirement Plan Prior Service (Cost) Credit	(161)	146	(155)
Amortization of Net Retirement Plan Actuarial Loss	602	672	827
Accretion of Net Retirement Plan Prior Service Credit	(65)	(112)	(109)
Other Comprehensive (Loss) Income	(272)	217	2,764
Comprehensive Income	$ 21,661	$ 22,109	$ 24,556