Allowance For Loan Loss Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Financing Receivable Allowance For Credit Loss Additional Information [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	$ 5,119		$ 5,575
Financing Receivable, Collectively Evaluated for Impairment	453,869		473,345
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Financing Receivable, Individually Evaluated for Impairment	286		327
Allowance for loan losses	5,119	$ 5,618	5,575
Loans and Leases Receivable, Gross, Carrying Amount	454,155	462,488	473,672
Commercial and Industrial Loans [Member]
Financing Receivable Allowance For Credit Loss Additional Information [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	816		798
Financing Receivable, Collectively Evaluated for Impairment	79,202		98,244
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Financing Receivable, Individually Evaluated for Impairment	0		0
Allowance for loan losses	816		798
Loans and Leases Receivable, Gross, Carrying Amount	79,202	82,585	98,244
Construction And Land Development Loans [Member]
Financing Receivable Allowance For Credit Loss Additional Information [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	590		582
Financing Receivable, Collectively Evaluated for Impairment	34,890		31,651
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Financing Receivable, Individually Evaluated for Impairment	0		0
Allowance for loan losses	590		582
Loans and Leases Receivable, Gross, Carrying Amount	34,890	33,514	31,651
Commercial Real Estate Loans, Total [Member]
Financing Receivable Allowance For Credit Loss Additional Information [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	2,823		3,120
Financing Receivable, Collectively Evaluated for Impairment	252,605		250,776
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Financing Receivable, Individually Evaluated for Impairment	193		216
Allowance for loan losses	2,823		3,120
Loans and Leases Receivable, Gross, Carrying Amount	252,798	255,136	250,992
Residential Real Estate Loans, Total [Member]
Financing Receivable Allowance For Credit Loss Additional Information [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	799		954
Financing Receivable, Collectively Evaluated for Impairment	80,112		84,943
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Financing Receivable, Individually Evaluated for Impairment	93		111
Allowance for loan losses	799		954
Loans and Leases Receivable, Gross, Carrying Amount	80,205	84,154	85,054
Consumer Installment and Revolving Loans [Member]
Financing Receivable Allowance For Credit Loss Additional Information [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	91		121
Financing Receivable, Collectively Evaluated for Impairment	7,060		7,731
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Financing Receivable, Individually Evaluated for Impairment	0		0
Allowance for loan losses	91		121
Loans and Leases Receivable, Gross, Carrying Amount	$ 7,060	$ 7,099	$ 7,731

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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- Definition

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

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=122038336&loc=d3e74567-122707

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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