Loans (Troubled Debt Restructurings on Financing Receivables) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan
TDRs | $	$ 10,790	$ 15,121
Less: TDRs included in non-accrual loans | $	(769)	(4,673)
Accrual TDR loans | $	$ 10,021	$ 10,448
Number of TDR loans | loan	16	22
Number of non-accrual TDR loans | loan	(1)	(6)
Number of accrual TDR loans | loan	15	16
Commercial Real Estate Portfolio Segment [Member]
TDRs | $	$ 9,273	$ 9,587
Number of TDR loans | loan	9	8
Residential First Mortgages Portfolio Segment [Member]
TDRs | $	$ 527	$ 545
Number of TDR loans | loan	2	2
Residential Rentals Portfolio Segment [Member]
TDRs | $	$ 221	$ 227
Number of TDR loans | loan	1	1
Construction And Land Development Portfolio Segment [Member]
TDRs | $	$ 729	$ 3,777
Number of TDR loans | loan	2	4
Commercial Portfolio Segment [Member]
TDRs | $	$ 4	$ 872
Number of TDR loans | loan	1	5
Commercial Equipment Portfolio Segment [Member]
TDRs | $	$ 36	$ 113
Number of TDR loans | loan	1	2