Impaired Loans Averages (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Impaired Financing Receivable, Average Recorded Investment [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 2,456	$ 2,071	$ 2,227	$ 2,659
Impaired Financing Receivable, Interest Income, Accrual Method	2	3	8	31
Commercial and Industrial Loans [Member]
Impaired Financing Receivable, Average Recorded Investment [Line Items]
Impaired Financing Receivable, Average Recorded Investment	126	26	55	36
Impaired Financing Receivable, Interest Income, Accrual Method	0	0	0	2
Construction And Land Development Loans [Member]
Impaired Financing Receivable, Average Recorded Investment [Line Items]
Impaired Financing Receivable, Average Recorded Investment	0	48	15	111
Impaired Financing Receivable, Interest Income, Accrual Method	0	0	0	0
Commercial Real Estate Owner Occupied Loans [Member]
Impaired Financing Receivable, Average Recorded Investment [Line Items]
Impaired Financing Receivable, Average Recorded Investment	182	465	186	850
Impaired Financing Receivable, Interest Income, Accrual Method	2	3	8	29
Commercial Real Estate Other Loans [Member]
Impaired Financing Receivable, Average Recorded Investment [Line Items]
Impaired Financing Receivable, Average Recorded Investment	2,148	1,532	1,971	1,662
Impaired Financing Receivable, Interest Income, Accrual Method	0	0	0	0
Commercial Real Estate Loans, Total [Member]
Impaired Financing Receivable, Average Recorded Investment [Line Items]
Impaired Financing Receivable, Average Recorded Investment	2,330	1,997	2,157	2,512
Impaired Financing Receivable, Interest Income, Accrual Method	$ 2	$ 3	$ 8	$ 29