Consolidated Statements of Income - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest income
Interest and fees on loans	$ 29,740,000	$ 25,525,000	$ 24,356,000
Interest and dividends on investment securities (AFS & HTM):
Taxable	6,270,000	5,454,000	5,219,000
Tax-exempt	1,957,000	1,949,000	2,009,000
Interest on trading securities	45,000	138,000	163,000
Interest on interest-bearing balances and other interest income	90,000	171,000	128,000
Total interest income	38,102,000	33,237,000	31,875,000
Interest on deposits
Interest-bearing demand	1,137,000	666,000	678,000
Money market	249,000	192,000	158,000
Savings	1,156,000	923,000	806,000
Time	1,512,000	1,497,000	1,548,000
Time of $100 or more	1,373,000	1,301,000	1,199,000
Interest on short-term borrowings	253,000	154,000	117,000
Total interest expense	5,680,000	4,733,000	4,506,000
Net interest income	32,422,000	28,504,000	27,369,000
Provision for loan losses	1,400,000	30,000	200,000
Net interest income after provision for loan losses	31,022,000	28,474,000	27,169,000
Non-interest income
Total other-than-temporary impairment loss on investment securities	(80,000)	(192,000)	(55,000)
Net other-than temporary impairment losses on investment securities	(80,000)	(192,000)	(55,000)
Net gain on sale of investment securities	1,580,000	866,000	838,000
Net gain on investment securities	1,500,000	674,000	783,000
Net (loss) gain on trading activities	27,000	(40,000)	33,000
Fees for services to customers	1,668,000	1,621,000	1,657,000
ATM and debit card	1,749,000	1,651,000	1,571,000
Retail brokerage and advisory	436,000	603,000	686,000
Bank-owned life insurance	345,000	308,000	307,000
Merchant	345,000	334,000	298,000
Net gain on sale of loans	375,000	320,000	356,000
Loss on sale of indirect lease financing portfolio		(223,000)
Other	442,000	419,000	341,000
Total non-interest income	6,887,000	5,667,000	6,032,000
Non-interest expense
Salaries and employee benefits	13,121,000	12,011,000	12,076,000
Net occupancy	1,789,000	1,750,000	1,762,000
Furniture and equipment	1,859,000	1,753,000	1,726,000
Marketing	914,000	806,000	805,000
Third party services	1,608,000	1,691,000	1,703,000
Telephone, postage and supplies	804,000	752,000	731,000
State taxes	687,000	666,000	681,000
FDIC insurance premiums	577,000	568,000	631,000
Other	2,361,000	2,166,000	2,283,000
Total non-interest expense	23,720,000	22,163,000	22,398,000
Income before income taxes	14,189,000	11,978,000	10,803,000
Provision for income taxes	5,900,000	3,054,000	2,570,000
Net income	$ 8,289,000	$ 8,924,000	$ 8,233,000
Earnings per share - basic	$ 2.42	$ 2.64	$ 2.47
Earnings per share - diluted	2.41	2.63	2.46
Cash dividends per share	$ 1.24	$ 1.20	$ 1.16