Loans and Allowance for Loan Losses - Past Due and Non-accrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	$ 217	$ 316
Non-Accrual	7,844	4,754
Loans held for investment	1,180,522	1,168,797
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	1,168,229	1,161,992
30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	4,232	1,735
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	3,111	982
Loans held for investment	205,657	199,022
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	201,949	197,828
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	597	212
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 held for investment	23,913	23,035
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	23,620	22,468
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	293	567
Residential real estate \| Mortgages
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	190	304
Non-Accrual	3,211	2,135
Loans held for investment	246,859	252,643
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	241,673	249,516
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	1,785	688
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	408	137
Loans held for investment	87,497	84,998
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	86,511	84,861
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	578	0
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	1,068	1,359
Loans held for investment	585,900	576,635
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	584,029	575,140
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	803	136
Installment and other consumer
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	27	12
Non-Accrual	46	141
Loans held for investment	30,696	32,464
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	30,447	32,179
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	$ 176	$ 132

Amount of financing receivable 90 days or more past due and still accruing.

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