QUARTERLY FINANCIAL DATA (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Quarterly Financial Data [Abstract]
Interest income	$ 18,400	$ 18,720	$ 19,598	$ 19,511	$ 19,635	$ 19,587	$ 18,686	$ 18,404	$ 76,229	$ 76,312	$ 72,403
Interest expense	3,474	3,880	4,296	4,477	4,566	4,566	4,306	4,129	16,127	17,567	16,774
Net interest income	14,926	14,840	15,302	15,034	15,069	15,021	14,380	14,275	60,102	58,745	55,629
Provision for loan losses	725	1,157	623	1,123	1,424	754	1,029	854	3,628	4,061	3,973
Noninterest income before net securities gains	1,646	1,653	1,680	1,596	1,559	1,569	1,622	1,538	6,575	6,288
Net gains on sales of securities	0	0	3,505	108	16	0	0	122	3,613	138	1,719
Noninterest expense before debt extinguishment costs	9,545	9,478	9,240	9,177	9,466	9,040	9,136	9,067	37,440	36,709
Debt extinguishment	0	0	3,812	0					3,812	0	0
Income before income taxes	6,302	5,858	6,812	6,438	5,754	6,796	5,837	6,014	25,410	24,401	23,763
Income tax expense	1,251	1,071	1,408	1,287	1,026	1,510	1,164	1,244	5,017	4,944	5,371
Net Income	5,051	4,787	5,404	5,151	4,728	5,286	4,673	4,770	20,393	19,457	18,392
Earnings per share [Abstract]
Basic (in dollars per share)	$ 0.56	$ 0.54	$ 0.61	$ 0.58	$ 0.54	$ 0.60	$ 0.53	$ 0.55	$ 2.29	$ 2.22	$ 2.33
Diluted (in dollars per share)	$ 0.56	$ 0.53	$ 0.60	$ 0.58	$ 0.53	$ 0.60	$ 0.53	$ 0.54	$ 2.27	$ 2.20	$ 2.30
Comprehensive income	$ 1,284	$ 8,788	$ 3,571	$ 5,802	$ 5,133	$ 13,054	$ 10,806	$ 9,568	$ 19,445	$ 38,561	$ 13,325