Allowance for Loan Losses (Schedule of Change in Allowance Methodology) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	$ 777	$ (625)	$ (188)
Construction And Farmland [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	(15)	(634)	(469)
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	30	(395)	81
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	283	41	246
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	388	478	13
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	(2)	19	(59)
All Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	95	$ 51	$ 6
Total Excluding Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	779
Calculated Provision Based on Prior Methodology [Member] | Construction And Farmland [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	(197)
Calculated Provision Based on Prior Methodology [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	(161)
Calculated Provision Based on Prior Methodology [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	140
Calculated Provision Based on Prior Methodology [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	326
Calculated Provision Based on Prior Methodology [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	(7)
Calculated Provision Based on Prior Methodology [Member] | All Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	102
Calculated Provision Based on Prior Methodology [Member] | Total Excluding Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	203
Difference [Member] | Construction And Farmland [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	182
Difference [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	191
Difference [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	143
Difference [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	62
Difference [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	5
Difference [Member] | All Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	(7)
Difference [Member] | Total Excluding Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (recovery of) loan losses	$ 576