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Loans and Allowance for Loan and Lease Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Impaired loans with no related allowance recorded, carrying amount	$ 5,608	$ 7,009
Impaired loans with no related allowance recorded, unpaid principal balance	5,608	7,009
Impaired loans, related allowances	72	74	$ 74
Impaired loans with an allowance recorded, carrying amount	100	102
Impaired loans with an allowance recorded, unpaid principal balance	100	102
Impaired loans, carrying amount	5,708	7,111
Impaired loans, unpaid principal balance	5,708		7,111
Impaired loans, average recorded investment	5,681	3,533
Impaired loans, interest income recognized	126	46
Impaired loans, interest income received	92	47
Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Impaired loans with no related allowance recorded, carrying amount	863	885
Impaired loans with no related allowance recorded, unpaid principal balance	863	885
Impaired loans, related allowances	11	12	12
Impaired loans with an allowance recorded, carrying amount	18	18
Impaired loans with an allowance recorded, unpaid principal balance	18	18
Impaired loans, carrying amount	881	903
Impaired loans, unpaid principal balance	881		903
Impaired loans, average recorded investment	911	923
Impaired loans, interest income recognized	2	10
Impaired loans, interest income received	2	10
Real Estate [Member] | Secured By Non-farm Non residential Properties [Member]
Impaired loans with no related allowance recorded, carrying amount	4,237	5,594
Impaired loans with no related allowance recorded, unpaid principal balance	4,237	5,594
Impaired loans, carrying amount	4,237	5,594
Impaired loans, unpaid principal balance	4,237		5,594
Impaired loans, average recorded investment	4,270	2,467
Impaired loans, interest income recognized	101	28
Impaired loans, interest income received	68	28
Commercial and Industrial Loans [Member]
Impaired loans with no related allowance recorded, carrying amount	508	530
Impaired loans with no related allowance recorded, unpaid principal balance	508	530
Impaired loans, related allowances	60	61	61
Impaired loans with an allowance recorded, carrying amount	59	60
Impaired loans with an allowance recorded, unpaid principal balance	59	60
Impaired loans, carrying amount	567	590
Impaired loans, unpaid principal balance	567		590
Impaired loans, average recorded investment	477	118
Impaired loans, interest income recognized	22	7
Impaired loans, interest income received	21	7
Direct Consumer [Member]
Impaired loans, related allowances	1	1	1
Impaired loans with an allowance recorded, carrying amount	23	24
Impaired loans with an allowance recorded, unpaid principal balance	23	24
Impaired loans, carrying amount	23	24
Impaired loans, unpaid principal balance	23		$ 24
Impaired loans, average recorded investment	23	25
Impaired loans, interest income recognized	1	1
Impaired loans, interest income received	$ 1	$ 2

X

- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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