Loans and the Allowance for Loan Losses, Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Receivables [Abstract]
Unpaid Principal Balance	$ 3,253	$ 4,200
Recorded Investment, Without Valuation Allowance	1,042	1,692
Recorded Investment, With Valuation Allowance	969	424
Associated Allowance	55	11
Average Recorded Investment	2,035	3,257
Interest Income Recognized	2	67
Mortgage Loans on Real Estate [Member]
Receivables [Abstract]
Unpaid Principal Balance	3,233	4,180
Recorded Investment, Without Valuation Allowance	1,025	1,672
Recorded Investment, With Valuation Allowance	969	424
Associated Allowance	55	11
Average Recorded Investment	2,016	3,235
Interest Income Recognized	2	66
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member]
Receivables [Abstract]
Unpaid Principal Balance	420	474
Recorded Investment, Without Valuation Allowance	75	366
Recorded Investment, With Valuation Allowance	316	87
Associated Allowance	38	1
Average Recorded Investment	395	458
Interest Income Recognized	0	10
Mortgage Loans on Real Estate [Member] \| Commercial [Member]
Receivables [Abstract]
Unpaid Principal Balance	2,597	3,490
Recorded Investment, Without Valuation Allowance	950	1,306
Recorded Investment, With Valuation Allowance	441	121
Associated Allowance	13	1
Average Recorded Investment	1,407	2,559
Interest Income Recognized	0	46
Mortgage Loans on Real Estate [Member] \| Construction [Member]
Receivables [Abstract]
Unpaid Principal Balance	83	83
Recorded Investment, Without Valuation Allowance	0	0
Recorded Investment, With Valuation Allowance	81	83
Associated Allowance	0	0
Average Recorded Investment	82	84
Interest Income Recognized	1	5
Mortgage Loans on Real Estate [Member] \| Second Mortgages [Member]
Receivables [Abstract]
Unpaid Principal Balance	133	133
Recorded Investment, Without Valuation Allowance	0	0
Recorded Investment, With Valuation Allowance	131	133
Associated Allowance	4	9
Average Recorded Investment	132	134
Interest Income Recognized	1	5
Commercial [Member] \| Commercial and Industrial Loans [Member]
Receivables [Abstract]
Unpaid Principal Balance	6	6
Recorded Investment, Without Valuation Allowance	5	6
Recorded Investment, With Valuation Allowance	0	0
Associated Allowance	0	0
Average Recorded Investment	6	7
Interest Income Recognized	0	0
Consumer [Member] \| Other Consumer Loans [Member]
Receivables [Abstract]
Unpaid Principal Balance	14	14
Recorded Investment, Without Valuation Allowance	12	14
Recorded Investment, With Valuation Allowance	0	0
Associated Allowance	0	0
Average Recorded Investment	13	15
Interest Income Recognized	$ 0	$ 1

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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