Loans and Allowance for Loan Losses, Recorded Investment in Loans by Portfolio Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Credit Quality Indicators [Abstract]
Loans	$ 503,091	$ 502,799
Pass [Member]
Credit Quality Indicators [Abstract]
Loans	468,747	469,634
Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	8,758	7,117
Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	25,586	26,048
Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Loss [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Commercial and Industrial [Member]
Credit Quality Indicators [Abstract]
Loans	25,041	24,413
Commercial and Industrial [Member] | Pass [Member]
Credit Quality Indicators [Abstract]
Loans	20,507	21,769
Commercial and Industrial [Member] | Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	3,170	1,152
Commercial and Industrial [Member] | Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	1,364	1,492
Commercial and Industrial [Member] | Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Commercial and Industrial [Member] | Loss [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Commercial Real Estate [Member]
Credit Quality Indicators [Abstract]
Loans	174,166	176,827
Commercial Real Estate [Member] | Pass [Member]
Credit Quality Indicators [Abstract]
Loans	165,439	167,625
Commercial Real Estate [Member] | Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	3,843	4,243
Commercial Real Estate [Member] | Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	4,884	4,959
Commercial Real Estate [Member] | Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Commercial Real Estate [Member] | Loss [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Construction and Land [Member]
Credit Quality Indicators [Abstract]
Loans	55,876	54,162
Construction and Land [Member] | Pass [Member]
Credit Quality Indicators [Abstract]
Loans	45,521	44,006
Construction and Land [Member] | Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	136	143
Construction and Land [Member] | Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	10,219	10,013
Construction and Land [Member] | Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Construction and Land [Member] | Loss [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Consumer [Member]
Credit Quality Indicators [Abstract]
Loans	4,624	5,068
Consumer [Member] | Pass [Member]
Credit Quality Indicators [Abstract]
Loans	4,621	5,065
Consumer [Member] | Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	3	3
Consumer [Member] | Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Consumer [Member] | Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Consumer [Member] | Loss [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Student [Member]
Credit Quality Indicators [Abstract]
Loans	10,212	10,677
Student [Member] | Pass [Member]
Credit Quality Indicators [Abstract]
Loans	10,212	10,677
Student [Member] | Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Student [Member] | Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Student [Member] | Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Student [Member] | Loss [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Residential Real Estate [Member]
Credit Quality Indicators [Abstract]
Loans	189,847	187,104
Residential Real Estate [Member] | Pass [Member]
Credit Quality Indicators [Abstract]
Loans	183,227	180,119
Residential Real Estate [Member] | Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	802	763
Residential Real Estate [Member] | Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	5,818	6,222
Residential Real Estate [Member] | Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Residential Real Estate [Member] | Loss [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Home Equity Lines of Credit [Member]
Credit Quality Indicators [Abstract]
Loans	43,325	44,548
Home Equity Lines of Credit [Member] | Pass [Member]
Credit Quality Indicators [Abstract]
Loans	39,220	40,373
Home Equity Lines of Credit [Member] | Special Mention [Member]
Credit Quality Indicators [Abstract]
Loans	804	813
Home Equity Lines of Credit [Member] | Substandard [Member]
Credit Quality Indicators [Abstract]
Loans	3,301	3,362
Home Equity Lines of Credit [Member] | Doubtful [Member]
Credit Quality Indicators [Abstract]
Loans	0	0
Home Equity Lines of Credit [Member] | Loss [Member]
Credit Quality Indicators [Abstract]
Loans	$ 0	$ 0