Loans and Related Allowance for Credit Losses (Loan Portfolio Summarized by the Past Due Status) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 3,887	$ 1,100
Current	414,188	382,804
Total loans	418,075	383,904	$ 382,616
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	321	215
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,863	776
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	703	109
Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	321	215
Commercial, Financial and Agricultural [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	49
Current	49,673	45,802
Total loans	49,722	45,802	48,551
Commercial, Financial and Agricultural [Member] | Commercial Portfolio Segment [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	49
Commercial Loan [Member] | Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	135,647	140,369	134,340
Commercial Loan [Member] | Real Estate Portfolio Segment [Member] | Excluding Loans Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	729	39
Current	134,409	140,139
Total loans	135,138	140,178
Commercial Loan [Member] | Real Estate Portfolio Segment [Member] | Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	148	28
Current	361	163
Total loans	509	191
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing		28
Commercial Loan [Member] | Real Estate Portfolio Segment [Member] | 30-59 Days Past Due [Member] | Excluding Loans Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	729	16
Commercial Loan [Member] | Real Estate Portfolio Segment [Member] | 60-89 Days Past Due [Member] | Excluding Loans Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		23
Commercial Loan [Member] | Real Estate Portfolio Segment [Member] | 60-89 Days Past Due [Member] | Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	148
Commercial Loan [Member] | Real Estate Portfolio Segment [Member] | Greater than 90 Days Past Due [Member] | Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		28
Construction Loan [Member] | Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	317
Current	36,633	28,403
Total loans	36,950	28,403	28,145
Construction Loan [Member] | Real Estate Portfolio Segment [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	317
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	167,198	146,888	147,783
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member] | Excluding Loans Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,043	838
Current	164,096	145,713
Total loans	166,139	146,551
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	60	64
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member] | Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	578	123
Current	481	214
Total loans	1,059	337
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	260	123
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member] | 30-59 Days Past Due [Member] | Excluding Loans Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,428	694
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member] | 30-59 Days Past Due [Member] | Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	318
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member] | 60-89 Days Past Due [Member] | Excluding Loans Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	555	80
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member] | Greater than 90 Days Past Due [Member] | Excluding Loans Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	60	64
Mortgage Loan [Member] | Real Estate Portfolio Segment [Member] | Greater than 90 Days Past Due [Member] | Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	260	123
Obligations of State and Political Subdivisions [Member] | Unallocated Financing Receivables [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	17,755	13,044
Total loans	17,755	13,044	13,862
Personal Loan [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	23	72
Current	10,780	9,326
Total loans	10,803	9,398	$ 9,935
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	1
Personal Loan [Member] | Consumer Portfolio Segment [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	22	66
Personal Loan [Member] | Consumer Portfolio Segment [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		$ 6
Personal Loan [Member] | Consumer Portfolio Segment [Member] | Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 1