Loans and Related Allowance for Loan Losses (Narrative) (Details)		12 Months Ended
Mar. 20, 2020 loan	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans		$ 422,661,000	$ 400,590,000
Period for trouble debt restructuring loan to be considered in default		30 days
Interest income on nonaccrual loans		$ 97,000	130,000
Troubled debt restructured loan		3,802,000	703,000
Reserves relating to TDR		0	0
Restructured loan balance in default status		0	0
Recorded charge-offs		$ 56,000	137,000
Credit quality indicators information		This analysis includes loans to commercial customers with an aggregate loan exposure greater than $500,000 and for lines of credit in excess of $50,000
Aggregate amount of demand deposits reclassified as loan balances		$ 50,000	70,000
Financing receivable - Allowance for loan losses		4,094,000	2,961,000
Paycheck Protection Program [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans		28,715,000
Financing receivable - Allowance for loan losses		$ 0
Number of Loans Funded under Paycheck Protection Program		508
Amount of Loan Funded under Paycheck Protection Program		$ 32,064,000
Number of loans forgiven by the SBA		47
Amount of loans forgiven by the SBA		$ 3,349,000
Deferred fees of PPP loans		475,000
Real Estate Portfolio Segment [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans		122,698,000	126,613,000
Recorded charge-offs		$ 0	15,000
Maximum loan-to-value ratio		80.00%
Financing receivable - Allowance for loan losses		$ 908,000	$ 754,000
Consumer Portfolio Segment [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans modifications, extensions of maturity dates			5 years 6 months
Consumer Portfolio Segment [Member] \| Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans		141,438,000	$ 150,538,000
Loans modifications, extensions of maturity dates			1 year 2 months 12 days
Restructured loan balance in default status		33,000
Recorded charge-offs		$ 7,000	$ 66,000
Maximum loan-to-value ratio		80.00%
Financing receivable - Allowance for loan losses		$ 1,200,000	1,081,000
Accruing Troubled Debt Restructurings [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Recorded charge-offs		0	16,000
Financing receivable - Allowance for loan losses		0	$ 0
Payment Deferral [Member] \| Covid-19 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans		$ 77,088,000
Number of borrowers approved for designated deferrals \| loan		227
Amount of loans completing deferment period		$ 5,052,000
Number of delinquent borrowers approved for designated deferrals \| loan	0	0
Number of borrowers remaining in payment deferral \| loan		4

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