Note 7 - Loans and Allowance for Credit Losses on Loans - Defaults on TDRs During Period (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Residential 1-4 Family Real Estate, Personal Residence [Member]
Number of defaults	1	1
Recorded Investment at Default Date	$ 22	$ 44
Home Equity Loan [Member]
Number of defaults	1	0
Recorded Investment at Default Date	$ 107	$ 0
Residential 1-4 Family Real Estate [Member]
Number of defaults	2	1
Recorded Investment at Default Date	$ 129	$ 44

Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 44
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-44

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

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Period Type:	duration