Note 7 - Loans and Allowance for Credit Losses on Loans - Financing Receivable, Troubled Debt Restructuring, Prior to ASU 2022-02 (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of Contracts	12	4
Pre-modification Recorded Investment	$ 1,521	$ 294
Post-modification Recorded Investment	$ 1,521	$ 294
Residential 1-4 Family Real Estate, Personal Residence [Member]
Number of Contracts	9	4
Pre-modification Recorded Investment	$ 692	$ 294
Post-modification Recorded Investment	$ 692	$ 294
Residential 1-4 Family Real Estate, Rental Large Loan [Member]
Number of Contracts	1	0
Pre-modification Recorded Investment	$ 671	$ 0
Post-modification Recorded Investment	$ 671	$ 0
Home Equity Loan [Member]
Number of Contracts	2	0
Pre-modification Recorded Investment	$ 158	$ 0
Post-modification Recorded Investment	$ 158	$ 0

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

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- Definition

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: 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 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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