Consolidated Statements of Stockholders' Equity (Unaudited) (USD $) In Thousands, unless otherwise specified	Total	Preferred Stock [Member]	Common Stock [Member]	Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]
Beginning balance at Dec. 31, 2011	$ 220,020	$ 400	$ 14,125	$ 156,184	$ 45,497	$ 3,814
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,446	0	0	0	5,446	0
Other comprehensive (loss) income	2,217	0	0	0	0	2,217
Dividends declared on preferred stock	(40)	0	0	0	(40)	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	35	0	3	32	0	0
Common stock share-based awards	423	0	0	423	0	0
Ending balance at Jun. 30, 2012	228,101	400	14,128	156,639	50,903	6,031
Beginning balance at Dec. 31, 2012	235,387	400	14,131	157,305	56,311	7,240
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	7,693	0	0	0	7,693	0
Other comprehensive (loss) income	(15,193)	0	0	0	0	(15,193)
Dividends declared on preferred stock	(40)	0	0	0	(40)	0
Common stock issued under stock option plans, including tax benefit	79	0	6	73	0	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	43	0	2	41	0	0
Common stock share-based awards	499	0	0	499	0	0
Ending balance at Jun. 30, 2013	$ 228,468	$ 400	$ 14,139	$ 157,918	$ 63,964	$ (7,953)