Condensed Consolidated Statements of Shareholders' Equity (unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	Preferred stock [Member]	Common stock [Member]	Retained earnings [Member]	Accumulated other comprehensive income (loss) [Member]	Total
Balance at Dec. 31, 2010	$ 25,334	$ 85,264	$ 71,307	$ (259)	$ 181,646
Balance (in shares) at Dec. 31, 2010		15,321,000
Comprehensive income:
Net income	0	0	4,076	0	4,076
Other comprehensive loss	0	0	0	(18)	(18)
Redemption of preferred stock issued to U.S. Treasury	(26,380)	0	0	0	(26,380)
Repurchase of warrant issued to U.S. Treasury	0	(1,625)	0	0	(1,625)
Preferred stock dividends and accretion	1,046	0	(1,084)	0	(38)
Cash dividends on common stock	0	0	(766)	0	(766)
Stock-based compensation expense	0	218	0	0	218
Issuance of common stock under stock plans	0	7	0	0	7
Issuance of common stock under stock plans (in shares)		12,000
Tax benefit associated with stock awards	0	5	0	0	5
Balance at Mar. 31, 2011	0	83,869	73,533	(277)	157,125
Balance (in shares) at Mar. 31, 2011		15,333
Balance at Dec. 31, 2011	0	84,564	83,107	3,080	170,751
Balance (in shares) at Dec. 31, 2011		15,398,000			15,398,197
Comprehensive income:
Net income	0	0	4,773	0	4,773
Other comprehensive loss	0	0	0	(207)	(207)
Cash dividends on common stock	0	0	(1,849)	0	(1,849)
Stock-based compensation expense	0	137	0	0	137
Issuance of common stock under stock plans	0	141	0	0	141
Issuance of common stock under stock plans (in shares)		21,000
Tax benefit associated with stock awards	0	11	0	0	11
Balance at Mar. 31, 2012	$ 0	$ 84,853	$ 86,031	$ 2,873	$ 173,757
Balance (in shares) at Mar. 31, 2012		15,419			15,419,472