Note 4 - Loans - Impaired Loan Balances by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Recorded investment, with no related allowance recorded	$ 2,218	$ 2,554
Unpaid principal balance, with no related allowance recorded	2,226	2,557
Average recorded investment, with no related allowance recorded	2,404	2,089
Interest income recognized, with no related allowance recorded	66	173
Recorded investment, with a related allowance recorded	14	298
Unpaid principal balance, with a related allowance recorded	7	292
Related allowance	7	30
Average recorded investment, with a related allowance recorded	116	818
Interest income recognized, with a related allowance recorded	3	39
Recorded investment	2,232	2,852
Unpaid principal balance	2,233	2,849
Average recorded investment	2,520	2,907
Interest income recognized	69	212
Commercial Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	18
Unpaid principal balance, with no related allowance recorded	0	18
Average recorded investment, with no related allowance recorded	4	23
Interest income recognized, with no related allowance recorded	0	6
Recorded investment, with a related allowance recorded	14	39
Unpaid principal balance, with a related allowance recorded	7	33
Related allowance	7	29
Average recorded investment, with a related allowance recorded	25	382
Interest income recognized, with a related allowance recorded	1	15
Recorded investment	14	57
Unpaid principal balance	7	51
Average recorded investment	29	405
Interest income recognized	1	21
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land Development [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment	0	0
Interest income recognized	0	0
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate [Member]
Recorded investment, with no related allowance recorded	8	286
Unpaid principal balance, with no related allowance recorded	5	283
Average recorded investment, with no related allowance recorded	71	357
Interest income recognized, with no related allowance recorded	1	27
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	8	286
Unpaid principal balance	5	283
Average recorded investment	71	357
Interest income recognized	1	27
Commercial Real Estate Portfolio Segment [Member] \| Non-owner Occupied Commercial Real Estate [Member]
Recorded investment, with no related allowance recorded	1,185	1,148
Unpaid principal balance, with no related allowance recorded	1,186	1,147
Average recorded investment, with no related allowance recorded	1,107	766
Interest income recognized, with no related allowance recorded	23	75
Recorded investment, with a related allowance recorded	0	122
Unpaid principal balance, with a related allowance recorded	0	122
Related allowance	0
Average recorded investment, with a related allowance recorded	30	180
Interest income recognized, with a related allowance recorded	0	15
Recorded investment	1,185	1,270
Unpaid principal balance	1,186	1,269
Average recorded investment	1,137	946
Interest income recognized	23	90
Residential Portfolio Segment [Member] \| Residential [Member]
Recorded investment, with no related allowance recorded	1,021	1,096
Unpaid principal balance, with no related allowance recorded	1,031	1,103
Average recorded investment, with no related allowance recorded	1,217	912
Interest income recognized, with no related allowance recorded	41	62
Recorded investment, with a related allowance recorded	0	137
Unpaid principal balance, with a related allowance recorded	0	137
Related allowance	0	1
Average recorded investment, with a related allowance recorded	61	256
Interest income recognized, with a related allowance recorded	2	9
Recorded investment	1,021	1,233
Unpaid principal balance	1,031	1,240
Average recorded investment	1,278	1,168
Interest income recognized	43	71
Residential Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Recorded investment, with no related allowance recorded	4	6
Unpaid principal balance, with no related allowance recorded	4	6
Average recorded investment, with no related allowance recorded	5	31
Interest income recognized, with no related allowance recorded	1	3
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	4	6
Unpaid principal balance	4	6
Average recorded investment	5	31
Interest income recognized	1	3
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment	0	0
Interest income recognized	$ 0	$ 0

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=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 50
-Paragraph 17
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