Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 11,043	$ 10,662	$ 10,350
Other comprehensive income (loss):
Net unrealized appreciation on securities available for sale, net of tax of $3,612, $451, and $1,239, respectively	7,012	875	2,407
Less reclassification adjustment for net gains related to securities available for sale included in net income, net of tax of ($914), ($723) and ($517), respectively	(1,775)	(1,404)	(1,004)
Add other-than-temporary impairment adjustment, net of tax of $950, $305 and $943, respectively	1,845	593	1,830
Less non-credit portion of other-than-temporary impairment losses, net of tax of $196, $0, and $448, respectively	(381)		(871)
Net unrealized depreciation and other amounts for interest rate derivatives, net of tax of $0, ($209) and ($172), respectively		(406)	(334)
Amortization of actuarial gain for supplemental executive retirement plan, net of related tax of $1, $3 and $3, respectively	2	6	6
Actuarial gain on supplemental executive retirement plan, net of related tax of $19, $24, and $0 respectively	37	47
Total other comprehensive income (loss)	6,740	(289)	2,034
Total comprehensive income	$ 17,783	$ 10,373	$ 12,384