Loans and Related Allowance for Loan Losses (Summary of Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 1,177,709	$ 1,058,323
Loans	$ 1,177,709	$ 1,058,323
Percent of loans	100.00%	100.00%
Mortgage Loans on Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 908,222	$ 854,925
Loans		$ 854,925
Percent of loans	77.12%	80.79%
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 204,366	$ 223,538
Loans		$ 223,538
Percent of loans	17.35%	21.12%
Mortgage Loans on Real Estate [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 452,677	$ 396,858
Loans		$ 396,858
Percent of loans	38.44%	37.50%
Mortgage Loans on Real Estate [Member] \| Construction and Land Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 159,766	$ 146,566
Loans		$ 146,566
Percent of loans	13.57%	13.85%
Mortgage Loans on Real Estate [Member] \| Second Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 6,488	$ 6,639
Loans		$ 6,639
Percent of loans	0.55%	0.63%
Mortgage Loans on Real Estate [Member] \| Multifamily [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 77,787	$ 72,978
Loans		$ 72,978
Percent of loans	6.60%	6.90%
Mortgage Loans on Real Estate [Member] \| Agriculture [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 7,138	$ 8,346
Loans		$ 8,346
Percent of loans	0.61%	0.79%
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 257,362	$ 191,183
Loans		$ 191,183
Percent of loans	21.85%	18.06%
Consumer Installment Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 10,606	$ 11,163
Loans		$ 11,163
Percent of loans	0.90%	1.05%
All Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 1,519	$ 1,052
Loans		$ 1,052
Percent of loans	0.13%	0.10%

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+ References

No definition available.

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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

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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.

+ 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
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

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