Consolidated Statements of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Preferred Stock [Member]	Common Stock [Member]	Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Dec. 31, 2010	$ 205,351	$ 400	$ 13,748	$ 151,545	$ 45,288	$ (5,630)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income	2,855	0	0	0	1,532	1,323
Dividends declared on preferred stock	(20)	0	0	0	(20)	0
Common stock issued under employee stock purchase plan	0	0	0	0	0	0
Proceeds from issuance of common stock in connection with dividend reinvestment and stock purchase plan	1,057	0	90	967	0	0
Common stock share-based awards	193	0	0	193	0	0
Ending balance at Mar. 31, 2011	209,436	400	13,838	152,705	46,800	(4,307)
Beginning balance at Dec. 31, 2011	220,020	400	14,125	156,184	45,497	3,814
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income	5,923	0	0	0	2,684	3,239
Dividends declared on preferred stock	(20)	0	0	0	(20)	0
Common stock issued under employee stock purchase plan	0	0	0	0	0	0
Proceeds from issuance of common stock in connection with dividend reinvestment and stock purchase plan	15	0	1	14	0	0
Common stock share-based awards	96	0	0	96	0	0
Ending balance at Mar. 31, 2012	$ 226,034	$ 400	$ 14,126	$ 156,294	$ 48,161	$ 7,053