Loans and Allowance for Loan Losses - Past Due and Non-accrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	$ 145	$ 162
Non-Accrual	5,431	5,414
Loans	1,154,652	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	1,145,869	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	3,207	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	1,747	1,857
Loans	204,759	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	202,850	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	162	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	26,082	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	26,082	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	140	156
Non-Accrual	2,803	2,720
Loans	248,059	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	243,864	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	1,252	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	151	153
Loans	109,766	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	109,143	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	472	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	508	474
Loans	534,121	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	532,539	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	1,074	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	5	6
Non-Accrual	222	210
Loans	31,865	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	31,391	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	$ 247	$ 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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+ 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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