Condensed Consolidated Statements of Income (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest income
Loans, including fees	$ 32,918,000	$ 30,746,000	$ 97,087,000	$ 86,406,000
Securities, taxable	1,718,000	1,322,000	4,938,000	3,885,000
Securities, tax-exempt	537,000	584,000	1,690,000	1,709,000
Other interest-earning assets	313,000	382,000	1,071,000	641,000
Total interest income	35,486,000	33,034,000	104,786,000	92,641,000
Interest expense
Deposits	3,574,000	2,652,000	9,921,000	6,543,000
Short-term borrowings	63,000	45,000	181,000	142,000
Federal Home Loan Bank advances	1,201,000	1,033,000	3,134,000	2,690,000
Subordinated debentures and other borrowings	808,000	660,000	2,286,000	1,920,000
Total interest expense	5,646,000	4,390,000	15,522,000	11,295,000
Net interest income	29,840,000	28,644,000	89,264,000	81,346,000
Provision for loan losses	400,000	1,000,000	1,100,000	2,350,000
Net interest income after provision for loan losses	29,440,000	27,644,000	88,164,000	78,996,000
Noninterest income:
Payroll services income	328,000	285,000	1,128,000	983,000
Earnings on bank owned life insurance	318,000	328,000	969,000	2,394,000
Other income	322,000	375,000	1,213,000	1,243,000
Total noninterest income	4,708,000	4,605,000	13,639,000	14,498,000
Noninterest expense
Salaries and benefits	12,932,000	11,636,000	38,027,000	33,796,000
Occupancy	1,648,000	1,598,000	5,049,000	4,707,000
Furniture and equipment depreciation, rent and maintenance	659,000	543,000	1,789,000	1,625,000
Data processing costs	2,150,000	2,071,000	6,415,000	6,155,000
Other expense	4,261,000	4,362,000	12,931,000	13,585,000
Total noninterest expenses	21,650,000	20,210,000	64,211,000	59,868,000
Income before federal income tax expense	12,498,000	12,039,000	37,592,000	33,626,000
Federal income tax expense	2,375,000	3,702,000	7,142,000	10,331,000
Net income	$ 10,123,000	$ 8,337,000	$ 30,450,000	$ 23,295,000
Basic earnings per share (in dollars per share)	$ 0.61	$ 0.51	$ 1.83	$ 1.41
Diluted earnings per share (in dollars per share)	0.61	0.51	1.83	1.41
Cash dividends per share (in dollars per share)	$ 0.24	$ 0.19	$ 0.68	$ 0.55
Average basic shares outstanding (in shares)	16,611,411	16,483,492	16,602,701	16,463,245
Average diluted shares outstanding (in shares)	16,619,295	16,494,540	16,610,544	16,474,534
Deposit Account [Member]
Noninterest income:
Noninterest income	$ 1,127,000	$ 1,076,000	$ 3,259,000	$ 3,148,000
Credit and Debit Card [Member]
Noninterest income:
Noninterest income	1,378,000	1,215,000	3,955,000	3,497,000
Mortgage Banking [Member]
Noninterest income:
Noninterest income	$ 1,235,000	$ 1,326,000	$ 3,115,000	$ 3,233,000