Loans and Allowance for Loan Losses - Past Due and Non-accrual Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	$ 197	$ 162
Non-Accrual	4,564	5,414
Loans	1,151,518	1,146,627
Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	1,145,421	1,136,236
30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	1,336	4,815
Commercial, financial, and agricultural
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	1,027	1,857
Loans	193,267	207,720
Commercial, financial, and agricultural \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	192,142	205,597
Commercial, financial, and agricultural \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	98	266
Residential real estate \| Construction
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	0	0
Loans	23,782	28,610
Residential real estate \| Construction \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	23,782	28,404
Residential real estate \| Construction \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	0	206
Residential real estate \| Mortgages
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	193	156
Non-Accrual	2,158	2,720
Loans	248,435	241,517
Residential real estate \| Mortgages \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	245,379	235,734
Residential real estate \| Mortgages \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	705	2,907
Commercial real estate \| Construction
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	145	153
Loans	124,389	106,784
Commercial real estate \| Construction \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	124,177	106,531
Commercial real estate \| Construction \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	67	100
Commercial real estate \| Mortgages
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	1,111	474
Loans	530,010	529,536
Commercial real estate \| Mortgages \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	528,539	527,968
Commercial real estate \| Mortgages \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	360	1,094
Installment and other consumer
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	4	6
Non-Accrual	123	210
Loans	31,635	32,460
Installment and other consumer \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	31,402	32,002
Installment and other consumer \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	$ 106	$ 242

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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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

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=82891408&loc=d3e4428-111522

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