Condensed Consolidated Statements of Income (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Interest income
Loans, including fees	$ 31,855,000	$ 28,927,000	$ 64,170,000	$ 55,660,000
Securities, taxable	1,618,000	1,285,000	3,220,000	2,563,000
Securities, tax-exempt	559,000	575,000	1,153,000	1,125,000
Other interest-earning assets	287,000	116,000	757,000	259,000
Total interest income	34,319,000	30,903,000	69,300,000	59,607,000
Interest expense
Deposits	3,262,000	2,023,000	6,347,000	3,891,000
Short-term borrowings	61,000	46,000	118,000	97,000
Federal Home Loan Bank advances	988,000	1,002,000	1,933,000	1,657,000
Subordinated debentures and other borrowings	783,000	639,000	1,478,000	1,260,000
Total interest expense	5,094,000	3,710,000	9,876,000	6,905,000
Net interest income	29,225,000	27,193,000	59,424,000	52,702,000
Provision for loan losses	700,000	750,000	700,000	1,350,000
Net interest income after provision for loan losses	28,525,000	26,443,000	58,724,000	51,352,000
Noninterest income:
Earnings on bank owned life insurance	321,000	328,000	652,000	2,066,000
Payroll services income	317,000	269,000	800,000	697,000
Other income	504,000	432,000	891,000	870,000
Total noninterest income	4,550,000	4,042,000	8,931,000	9,893,000
Noninterest expense
Salaries and benefits	12,757,000	10,888,000	25,094,000	22,160,000
Occupancy	1,629,000	1,554,000	3,401,000	3,108,000
Furniture and equipment depreciation, rent and maintenance	582,000	546,000	1,130,000	1,081,000
Data processing costs	2,137,000	2,072,000	4,265,000	4,083,000
Other expense	4,309,000	4,822,000	8,671,000	9,226,000
Total noninterest expenses	21,414,000	19,882,000	42,561,000	39,658,000
Income before federal income tax expense	11,661,000	10,603,000	25,094,000	21,587,000
Federal income tax expense	2,215,000	3,260,000	4,767,000	6,629,000
Net income	$ 9,446,000	$ 7,343,000	$ 20,327,000	$ 14,958,000
Basic earnings per share (in dollars per share)	$ 0.57	$ 0.45	$ 1.22	$ 0.91
Diluted earnings per share (in dollars per share)	0.57	0.45	1.22	0.91
Cash dividends per common share (in dollars per share)	$ 0.22	$ 0.18	$ 0.44	$ 0.36
Average basic shares outstanding (in shares)	16,601,400	16,471,060	16,598,274	16,452,954
Average diluted shares outstanding (in shares)	16,610,819	16,485,356	16,607,593	16,467,384
Deposit Account [Member]
Noninterest income:
Noninterest income	$ 1,079,000	$ 1,054,000	$ 2,132,000	$ 2,072,000
Credit and Debit Card [Member]
Noninterest income:
Noninterest income	1,334,000	1,176,000	2,577,000	2,282,000
Mortgage Banking [Member]
Noninterest income:
Noninterest income	$ 995,000	$ 783,000	$ 1,879,000	$ 1,906,000