Loans and Allowance for Loan Losses, Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Unpaid Principal Balance	$ 4,200	$ 11,595
Recorded Investment, Without Valuation Allowance	1,692	6,411
Recorded Investment, With Valuation Allowance	424	2,033
Associated Allowance	11	481
Average Recorded Investment	3,257	8,866
Interest Income Recognized	67	149
Mortgage Loans on Real Estate [Member]
Receivables [Abstract]
Unpaid Principal Balance	4,180	11,211
Recorded Investment, Without Valuation Allowance	1,672	6,057
Recorded Investment, With Valuation Allowance	424	2,033
Associated Allowance	11	481
Average Recorded Investment	3,235	8,572
Interest Income Recognized	66	144
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member]
Receivables [Abstract]
Unpaid Principal Balance	474	1,542
Recorded Investment, Without Valuation Allowance	366	1,519
Recorded Investment, With Valuation Allowance	87	89
Associated Allowance	1	39
Average Recorded Investment	458	1,416
Interest Income Recognized	10	11
Mortgage Loans on Real Estate [Member] \| Commercial [Member]
Receivables [Abstract]
Unpaid Principal Balance	3,490	9,333
Recorded Investment, Without Valuation Allowance	1,306	4,538
Recorded Investment, With Valuation Allowance	121	1,611
Associated Allowance	1	317
Average Recorded Investment	2,559	6,822
Interest Income Recognized	46	123
Mortgage Loans on Real Estate [Member] \| Construction [Member]
Receivables [Abstract]
Unpaid Principal Balance	83	89
Recorded Investment, Without Valuation Allowance	0	0
Recorded Investment, With Valuation Allowance	83	88
Associated Allowance	0	14
Average Recorded Investment	84	88
Interest Income Recognized	5	4
Mortgage Loans on Real Estate [Member] \| Second Mortgages [Member]
Receivables [Abstract]
Unpaid Principal Balance	133	247
Recorded Investment, Without Valuation Allowance	0	0
Recorded Investment, With Valuation Allowance	133	245
Associated Allowance	9	111
Average Recorded Investment	134	246
Interest Income Recognized	5	6
Commercial [Member] \| Commercial and Industrial Loans [Member]
Receivables [Abstract]
Unpaid Principal Balance	6	362
Recorded Investment, Without Valuation Allowance	6	354
Recorded Investment, With Valuation Allowance	0	0
Associated Allowance	0	0
Average Recorded Investment	7	273
Interest Income Recognized	0	4
Consumer [Member] \| Other Consumer Loans [Member]
Receivables [Abstract]
Unpaid Principal Balance	14	22
Recorded Investment, Without Valuation Allowance	14	0
Recorded Investment, With Valuation Allowance	0	0
Associated Allowance	0	0
Average Recorded Investment	15	21
Interest Income Recognized	$ 1	$ 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
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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