Loans and Allowance for Loan and Lease Losses - Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Impaired loans with no related allowance recorded, carrying amount	$ 7,009	$ 2,861
Impaired loans with no related allowance recorded, unpaid principal balance	7,009	2,861
Impaired loans, related allowances	74	227
Impaired loans with no related allowance recorded, carrying amount	102	256
Impaired loans with no related allowance recorded, unpaid principal balance	102	256
Impaired loans, carrying amount	7,111	3,117
Impaired loans, unpaid principal balance	7,111	3,117
Impaired loans, average recorded investment	3,533	2,876
Impaired loans, interest income recognized	46	86
Impaired loans, interest income received	47	86
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member]
Impaired loans, average recorded investment		181
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Impaired loans with no related allowance recorded, carrying amount	885	984
Impaired loans with no related allowance recorded, unpaid principal balance	885	984
Impaired loans, related allowances	12	14
Impaired loans with no related allowance recorded, carrying amount	18	21
Impaired loans with no related allowance recorded, unpaid principal balance	18	21
Impaired loans, carrying amount	903	1,005
Impaired loans, unpaid principal balance	903	1,005
Impaired loans, average recorded investment	923	1,021
Impaired loans, interest income recognized	10	48
Impaired loans, interest income received	10	48
Real Estate [Member] \| Secured By Non-farm Non residential Properties [Member]
Impaired loans with no related allowance recorded, carrying amount	5,594	1,877
Impaired loans with no related allowance recorded, unpaid principal balance	5,594	1,877
Impaired loans, carrying amount	5,594	1,877
Impaired loans, unpaid principal balance	5,594	1,877
Impaired loans, average recorded investment	2,467	645
Impaired loans, interest income recognized	28	29
Impaired loans, interest income received	28	29
Commercial and Industrial Loans [Member]
Impaired loans with no related allowance recorded, carrying amount	530
Impaired loans with no related allowance recorded, unpaid principal balance	530
Impaired loans, related allowances	61	206
Impaired loans with no related allowance recorded, carrying amount	60	206
Impaired loans with no related allowance recorded, unpaid principal balance	60	206
Impaired loans, carrying amount	590	206
Impaired loans, unpaid principal balance	590	206
Impaired loans, average recorded investment	118	991
Impaired loans, interest income recognized	7	7
Impaired loans, interest income received	7	7
Direct Consumer [Member]
Impaired loans, related allowances	1	7
Impaired loans with no related allowance recorded, carrying amount	24	29
Impaired loans with no related allowance recorded, unpaid principal balance	24	29
Impaired loans, carrying amount	24	29
Impaired loans, unpaid principal balance	24	29
Impaired loans, average recorded investment	25	38
Impaired loans, interest income recognized	1	2
Impaired loans, interest income received	$ 2	$ 2

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
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