Note 5 - ACL on LHFI - Net Charge-offs (Recoveries) by Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Current year charge-off	$ 17
Year two charge-off	28
Year three charge-off	6
Year four charge-off	4
Year five charge-off	5
Prior, charge-off	95
Revolving loans charge off	98
Chargeoffs	253	$ 179
Real Estate Portfolio Segment [Member]
Current year charge-off	0
Year two charge-off	0
Year three charge-off	0
Year four charge-off	0
Year five charge-off	5
Prior, charge-off	17
Revolving loans charge off	0
Chargeoffs	22	8
Real Estate Portfolio Segment [Member] \| Commercial Real Estate [Member]
Current year charge-off	0
Year two charge-off	0
Year three charge-off	0
Year four charge-off	0
Year five charge-off	5
Prior, charge-off	17
Revolving loans charge off	0
Chargeoffs	22
Commercial Portfolio Segment [Member]
Current year charge-off	5
Year two charge-off	0
Year three charge-off	0
Year four charge-off	0
Year five charge-off	0
Prior, charge-off	78
Revolving loans charge off	0
Chargeoffs	83	61
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member]
Current year charge-off	5
Year two charge-off	0
Year three charge-off	0
Year four charge-off	0
Year five charge-off	0
Prior, charge-off	78
Revolving loans charge off	0
Chargeoffs	83
Consumer Portfolio Segment [Member]
Chargeoffs	148	$ 110
Consumer Portfolio Segment [Member] \| Other Consumer Loans [Member]
Current year charge-off	12
Year two charge-off	28
Year three charge-off	6
Year four charge-off	4
Year five charge-off	0
Prior, charge-off	0
Revolving loans charge off	0
Chargeoffs	50
Consumer Portfolio Segment [Member] \| Credit Card Receivable [Member]
Current year charge-off	0
Year two charge-off	0
Year three charge-off	0
Year four charge-off	0
Year five charge-off	0
Prior, charge-off	0
Revolving loans charge off	98
Chargeoffs	$ 98

Amount of writeoff of financing receivable, charged against allowance for credit loss.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-SubTopic 10
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-11B

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