Loans and Related Allowance for Credit Losses (Allowance for Loan Losses and Related Investments in Loans Receivable) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	$ 2,961	$ 3,034
Provision for loan losses	356	15
Charge-offs	(21)	(73)
Recoveries	37	18
Ending balance	3,333	2,994
Loans allocated by: individually evaluated for impairment	5,648		$ 2,516
Loans allocated by: collectively evaluated for impairment	383,329		397,004
Financing receivable - Loans allocated	390,014		400,590
Allowance for loan losses allocated by: individually evaluated for impairment	125
Allowance for loan losses allocated by: collectively evaluated for impairment	3,208		2,961
Financing receivable - Allowance for loan losses	3,333		2,961
Commercial, Financial and Agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	321	275
Provision for loan losses	112	6
Recoveries		2
Ending balance	433	283
Loans allocated by: individually evaluated for impairment	562
Loans allocated by: collectively evaluated for impairment	48,271		51,785
Financing receivable - Loans allocated	48,833		51,785
Allowance for loan losses allocated by: individually evaluated for impairment	118
Allowance for loan losses allocated by: collectively evaluated for impairment	315		321
Financing receivable - Allowance for loan losses	433		275
Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	754	1,074
Provision for loan losses	4	(23)
Charge-offs		(15)
Recoveries		7
Ending balance	758	1,043
Loans allocated by: individually evaluated for impairment	3,836		1,206
Loans allocated by: collectively evaluated for impairment	114,073		125,041
Financing receivable - Loans allocated	118,265		126,613
Allowance for loan losses allocated by: collectively evaluated for impairment	758		754
Financing receivable - Allowance for loan losses	758		1,074
Construction Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	718	558
Provision for loan losses	154	14
Recoveries	32
Ending balance	904	572
Loans allocated by: collectively evaluated for impairment	51,108		46,459
Financing receivable - Loans allocated	51,108		46,459
Allowance for loan losses allocated by: collectively evaluated for impairment	904		718
Financing receivable - Allowance for loan losses	904		558
Obligations of State and Political Subdivisions [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	17	20
Provision for loan losses	6	1
Ending balance	23	21
Loans allocated by: collectively evaluated for impairment	16,621		16,377
Financing receivable - Loans allocated	16,621		16,377
Allowance for loan losses allocated by: collectively evaluated for impairment	23		17
Financing receivable - Allowance for loan losses	23		20
Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	1,081	1,035
Provision for loan losses	65	12
Charge-offs		(47)
Recoveries	1	5
Ending balance	1,147	1,005
Loans allocated by: individually evaluated for impairment	1,250		1,296
Loans allocated by: collectively evaluated for impairment	145,295		148,538
Financing receivable - Loans allocated	147,226		150,538
Allowance for loan losses allocated by: individually evaluated for impairment	7
Allowance for loan losses allocated by: collectively evaluated for impairment	1,140		1,081
Financing receivable - Allowance for loan losses	1,147		1,035
Personal Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	70	72
Provision for loan losses	15	5
Charge-offs	(21)	(11)
Recoveries	4	4
Ending balance	68	$ 70
Loans allocated by: individually evaluated for impairment			14
Loans allocated by: collectively evaluated for impairment	7,961		8,804
Financing receivable - Loans allocated	7,961		8,818
Allowance for loan losses allocated by: collectively evaluated for impairment	68		70
Financing receivable - Allowance for loan losses	68		72
Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	1,037		1,070
Acquired with Credit Deterioration [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	356		366
Acquired with Credit Deterioration [Member] \| Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	$ 681		$ 704

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount, before allowance for credit loss, of financing receivable.

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Amount of expense related to estimated loss from loan and lease transactions.

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