Loans and Related Allowance for Loan Losses (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	$ 400,590,000	$ 417,631,000
Period for trouble debt restructuring loan to be considered in default	30 days
Interest income on nonaccrual loans	$ 130,000	311,000
Interest income on nonaccrual loans due to pay off and pay down of two loans		175,000
Troubled debt restructured loan	703,000	445,000
Reserves relating to TDR	0	0
Restructured loan balance in default status	0	0
Recorded charge-offs	$ 137,000	285,000
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	$ 70,000	75,000
Real Estate Portfolio Segment [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	126,613,000	141,295,000
Recorded charge-offs	$ 15,000	60,000
Maximum loan-to-value ratio	80.00%
Real Estate Portfolio Segment [Member] \| Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	$ 150,538,000	163,548,000
Loans modifications, extensions of maturity dates	5 years 6 months
Restructured loan balance in default status	$ 36,000
Consumer Portfolio Segment [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans modifications, extensions of maturity dates	1 year 2 months 12 days
Consumer Portfolio Segment [Member] \| Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	$ 150,538,000	$ 163,548,000
Loans modifications, extensions of maturity dates		5 years 3 months 18 days
Recorded charge-offs	66,000	$ 183,000
Accruing Troubled Debt Restructurings [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Recorded charge-offs	$ 16,000	$ 0

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Amount of specific reserve of financing receivables related to troubled debt restructuring.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Loans and leases receivable period for trouble debt restructuring loan to be considered in default.

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Maximum Loan To Value Ratio

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Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss.

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Amount of financing receivable modified as troubled debt restructuring.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of expense recognized during the period for the foreclosure on real estate assets.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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