Premises, Furniture, and Equipment (Schedule of Premises, Furniture and Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Total Premises, Furniture and Equipment	$ 100,519	$ 92,761
Less: Accumulated Depreciation	(46,273)	(44,531)
Total	54,246	48,230
Depreciation expense	3,933	3,774	$ 3,310
Land
Property, Plant and Equipment [Line Items]
Total Premises, Furniture and Equipment	11,541	10,255
Buildings and Improvements
Property, Plant and Equipment [Line Items]
Total Premises, Furniture and Equipment	60,076	55,676
Furniture and Equipment
Property, Plant and Equipment [Line Items]
Total Premises, Furniture and Equipment	$ 28,902	$ 26,830