Income Taxes (Tax Rate Reconciliation) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Computed expected tax expense	$ 9,967,000	$ 8,961,000	$ 8,259,000
Increase (decrease) in income taxes resulting from:
Tax reform	3,524,000	0	0
State income taxes, net of federal benefit	127,000	117,000	92,000
Tax exempt income and interest	(1,305,000)	(409,000)	(257,000)
Merger related expenses, nondeductible	550,000	344,000	0
Low income housing tax credits	(586,000)	0	0
Other	(300,000)	187,000	83,000
Total income tax expense (benefit)	11,977,000	9,200,000	$ 8,177,000
Interest and penalties accrued	$ 0	$ 0