CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Interest and dividend income:
Loans	$ 47,777	$ 45,660	$ 39,753
Investment securities:
Taxable	16,662	16,879	18,938
Nontaxable	11,873	9,864	7,595
Total interest and dividend income	76,312	72,403	66,286
Interest expense:
Savings, NOW and money market deposits	4,035	4,049	5,287
Time deposits	6,052	5,977	6,485
Short-term borrowings	93	108	221
Long-term debt	7,387	6,640	6,341
Total interest income	17,567	16,774	18,334
Net interest income	58,745	55,629	47,952
Provision for loan losses	4,061	3,973	4,285
Net interest income after provision for loan losses	54,684	51,656	43,667
Noninterest income:
Investment Management Division income	1,539	1,465	1,484
Service charges on deposit accounts	3,186	3,465	3,503
Net gains on sales of available-for-sale securities	138	1,719	1,428
Other	1,563	1,284	1,339
Total noninterest income	6,426	7,933	7,754
Noninterest expense:
Salaries	15,785	15,458	14,869
Employee benefits	5,066	5,303	5,827
Occupancy and equipment expense	7,148	6,486	6,025
Other operating expenses	8,710	8,579	8,119
Total noninterest expense	36,709	35,826	34,840
Income before income taxes	24,401	23,763	16,581
Income tax expense	4,944	5,371	3,118
Net Income	$ 19,457	$ 18,392	$ 13,463
Weighted average:
Common shares (in shares)	8,761,895	7,899,241	7,203,064
Dilutive stock options and restricted stock units (in shares)	93,069	108,436	106,520
Weighted average number of shares (in shares)	8,854,964	8,007,677	7,309,584
Earnings per share:
Basic (in dollars per share)	$ 2.22	$ 2.33	$ 1.87
Diluted (in dollars per share)	$ 2.20	$ 2.30	$ 1.84
Cash dividends declared per share (in dollars per share)	$ 0.90	$ 0.84	$ 0.76