Loans (Loans Maturing in Portfolio Based on Contractual Terms) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Contract receivable, due within one year	$ 183,796	$ 164,203
Contract receivable, due after one year through five years	210,999	177,601
Contract receivable, due in more than five years	694,187	577,090
Commercial Real Estate Portfolio Segment [Member]
Contract receivable, due within one year	86,782	50,413
Contract receivable, due after one year through five years	128,431	109,037
Contract receivable, due in more than five years	451,892	379,438
Residential First Mortgages Portfolio Segment [Member]
Contract receivable, due within one year	8,501	6,989
Contract receivable, due after one year through five years	34,592	28,245
Contract receivable, due in more than five years	127,911	96,167
Residential Rentals Portfolio Segment [Member]
Contract receivable, due within one year	3,847	3,517
Contract receivable, due after one year through five years	17,911	16,375
Contract receivable, due in more than five years	80,139	73,265
Construction And Land Development Portfolio Segment [Member]
Contract receivable, due within one year	23,674	27,609
Contract receivable, due after one year through five years	10,212	5,025
Contract receivable, due in more than five years	3,048	3,555
Home Equity And Second Mortgages Portfolio Segment [Member]
Contract receivable, due within one year	296	330
Contract receivable, due after one year through five years	877	1,134
Contract receivable, due in more than five years	20,226	20,252
Commercial Portfolio Segment [Member]
Contract receivable, due within one year	50,484	67,246
Consumer Portfolio Segment [Member]
Contract receivable, due within one year	163	200
Contract receivable, due after one year through five years	164	150
Contract receivable, due in more than five years	95	16
Commercial Equipment Portfolio Segment [Member]
Contract receivable, due within one year	10,049	7,899
Contract receivable, due after one year through five years	18,812	17,635
Contract receivable, due in more than five years	$ 10,876	$ 4,397