Note 5 - Loans and Leases - Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Unpaid principal balance	$ 4,602	$ 6,840
Recorded investment with allowance	1,676	3,504
Recorded investment with no allowance	2,192	2,431
Total recorded investment	3,868	5,935
Related allowance	161	1,259
Average recorded investment	4,483	5,915	$ 5,500
Interest income recognized	282	280	147
Cash basis interest income recognized	0	0	$ 0
Commercial Portfolio Segment [Member]
Unpaid principal balance	942	218
Recorded investment with allowance	139	18
Recorded investment with no allowance	580	136
Total recorded investment	719	154
Related allowance	48	18
Average recorded investment	468	380
Interest income recognized	0	2
Cash basis interest income recognized	0	0
Commercial Real Estate Portfolio Segment [Member] \| Non-owner Occupied [Member]
Unpaid principal balance	762	2,470
Recorded investment with allowance	215	1,674
Recorded investment with no allowance	547	796
Total recorded investment	762	2,470
Related allowance	42	474
Average recorded investment	1,263	2,698
Interest income recognized	104	195
Cash basis interest income recognized	0	0
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied [Member]
Unpaid principal balance	2,347	3,185
Recorded investment with allowance	1,304	1,802
Recorded investment with no allowance	716	762
Total recorded investment	2,020	2,564
Related allowance	70	763
Average recorded investment	2,279	1,883
Interest income recognized	125	55
Cash basis interest income recognized	0	0
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Average recorded investment	0	0
Interest income recognized	0	0
Cash basis interest income recognized	0	0
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Unpaid principal balance	33	33
Recorded investment with allowance	0	0
Recorded investment with no allowance	0	0
Total recorded investment	0	0
Related allowance	0	0
Average recorded investment	0	28
Interest income recognized	0	6
Cash basis interest income recognized	0	0
Consumer Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Unpaid principal balance	255	137
Recorded investment with allowance	0	0
Recorded investment with no allowance	211	97
Total recorded investment	211	97
Related allowance	0	0
Average recorded investment	153	202
Interest income recognized	7	20
Cash basis interest income recognized	0	0
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Unpaid principal balance	213	98
Recorded investment with allowance	18	10
Recorded investment with no allowance	135	68
Total recorded investment	153	78
Related allowance	1	4
Average recorded investment	162	42
Interest income recognized	5	2
Cash basis interest income recognized	0	0
Consumer Portfolio Segment [Member] \| Direct Financing Lease [Member]
Average recorded investment	0	0
Interest income recognized	0	0
Cash basis interest income recognized	0	0
Consumer Portfolio Segment [Member] \| Other Loan [Member]
Average recorded investment	0	0
Interest income recognized	0	0
Cash basis interest income recognized	0	0
Residential Portfolio Segment [Member] \| Construction Loans [Member]
Average recorded investment	0	0
Interest income recognized	0	0
Cash basis interest income recognized	0	0
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Unpaid principal balance	50	699
Recorded investment with allowance	0	0
Recorded investment with no allowance	3	572
Total recorded investment	3	572
Related allowance	0	0
Average recorded investment	158	682
Interest income recognized	41	0
Cash basis 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 https://asc.fasb.org/extlink&oid=123577603&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 https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

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