Loans and Related Allowance for Credit Losses (Allowance for Loan Losses and Related Investments in Loans Receivable) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	$ 3,333	$ 2,994	$ 2,961	$ 3,034
Provision for loan losses	196	(459)	552	(444)
Charge-offs	(7)	(28)	(28)	(101)
Recoveries	36	508	73	526
Ending balance	3,558	3,015	3,558	3,015
Loans allocated by: individually evaluated for impairment	4,620		4,620		$ 2,516
Loans allocated by: collectively evaluated for impairment	414,959		414,959		397,004
Financing receivable - Loans allocated	420,596		420,596		400,590
Allowance for loan losses allocated by: individually evaluated for impairment	2		2		0
Allowance for loan losses allocated by: collectively evaluated for impairment	3,556		3,556		2,961
Financing receivable - Allowance for loan losses	3,558		3,558		2,961
Commercial, Financial and Agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	433	283	321	275
Provision for loan losses	(122)	(10)	(10)	(4)
Charge-offs	0	0	0	0
Recoveries	0	1	0	3
Ending balance	311	274	311	274
Loans allocated by: individually evaluated for impairment	549		549		0
Loans allocated by: collectively evaluated for impairment	75,815		75,815		51,785
Financing receivable - Loans allocated	76,364		76,364		51,785
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: collectively evaluated for impairment	311		311		321
Financing receivable - Allowance for loan losses	311		311		275
Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	758	1,043	754	1,074
Provision for loan losses	120	(312)	124	(335)
Charge-offs	0	0	0	(15)
Recoveries	0	307	0	314
Ending balance	878	1,038	878	1,038
Loans allocated by: individually evaluated for impairment	3,160		3,160		1,206
Loans allocated by: collectively evaluated for impairment	120,067		120,067		125,041
Financing receivable - Loans allocated	123,581		123,581		126,613
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: collectively evaluated for impairment	878		878		754
Financing receivable - Allowance for loan losses	878		878		1,074
Construction Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	904	572	718	558
Provision for loan losses	203	(177)	357	(163)
Charge-offs	0	0	0	0
Recoveries	30	193	62	193
Ending balance	1,137	588	1,137	588
Loans allocated by: individually evaluated for impairment	0		0		0
Loans allocated by: collectively evaluated for impairment	54,000		54,000		46,459
Financing receivable - Loans allocated	54,000		54,000		46,459
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: collectively evaluated for impairment	1,137		1,137		718
Financing receivable - Allowance for loan losses	1,137		1,137		558
Obligations of State and Political Subdivisions [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	23	21	17	20
Provision for loan losses	(1)	1	5	2
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	22	22	22	22
Loans allocated by: individually evaluated for impairment	0		0		0
Loans allocated by: collectively evaluated for impairment	16,390		16,390		16,377
Financing receivable - Loans allocated	16,390		16,390		16,377
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: collectively evaluated for impairment	22		22		17
Financing receivable - Allowance for loan losses	22		22		20
Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	1,147	1,005	1,081	1,035
Provision for loan losses	4	16	69	28
Charge-offs	(4)	(2)	(4)	(49)
Recoveries	2	0	3	5
Ending balance	1,149	1,019	1,149	1,019
Loans allocated by: individually evaluated for impairment	911		911		1,296
Loans allocated by: collectively evaluated for impairment	141,562		141,562		148,538
Financing receivable - Loans allocated	143,136		143,136		150,538
Allowance for loan losses allocated by: individually evaluated for impairment	2		2		0
Allowance for loan losses allocated by: collectively evaluated for impairment	1,147		1,147		1,081
Financing receivable - Allowance for loan losses	1,149		1,149		1,035
Personal Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	68	70	70	72
Provision for loan losses	(8)	23	7	28
Charge-offs	(3)	(26)	(24)	(37)
Recoveries	4	7	8	11
Ending balance	61	$ 74	61	$ 74
Loans allocated by: individually evaluated for impairment	0		0		14
Loans allocated by: collectively evaluated for impairment	7,125		7,125		8,804
Financing receivable - Loans allocated	7,125		7,125		8,818
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: collectively evaluated for impairment	61		61		70
Financing receivable - Allowance for loan losses	61		61		72
Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	1,017		1,017		1,070
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Acquired with Credit Deterioration [Member] \| Commercial, Financial and Agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Acquired with Credit Deterioration [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	354		354		366
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Acquired with Credit Deterioration [Member] \| Construction Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Acquired with Credit Deterioration [Member] \| Obligations of State and Political Subdivisions [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Acquired with Credit Deterioration [Member] \| Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	663		663		704
Allowance for loan losses allocated by: individually evaluated for impairment	0		0		0
Acquired with Credit Deterioration [Member] \| Personal Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans allocated by: individually evaluated for impairment	0		0		0
Allowance for loan losses allocated by: individually evaluated for impairment	$ 0		$ 0		$ 0

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 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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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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