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Note 3 - Loans and Allowance for Credit Losses - Loans Modified as Troubled Debt Restructurings (Details)	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of Contracts	10	18
Pre- Modification Recorded Principal Balance	$ 7,351,000	$ 4,333,000
Post- Modification Recorded Principal Balance	$ 7,350,000	$ 4,329,000
Commercial Portfolio Segment [Member]
Number of Contracts	3	12
Pre- Modification Recorded Principal Balance	$ 6,593,000	$ 3,802,000
Post- Modification Recorded Principal Balance	$ 6,593,000	$ 3,801,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Number of Contracts	3	10
Pre- Modification Recorded Principal Balance	$ 6,593,000	$ 3,017,000
Post- Modification Recorded Principal Balance	$ 6,593,000	$ 3,016,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Number of Contracts	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Number of Contracts	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 692,000
Post- Modification Recorded Principal Balance	$ 0	$ 692,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Number of Contracts	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Number of Contracts	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 93,000
Post- Modification Recorded Principal Balance	$ 0	$ 93,000
Retail Portfolio Segment [Member]
Number of Contracts	7	6
Pre- Modification Recorded Principal Balance	$ 758,000	$ 531,000
Post- Modification Recorded Principal Balance	$ 757,000	$ 528,000
Retail Portfolio Segment [Member] | Home Equity Loan [Member]
Number of Contracts	0	4
Pre- Modification Recorded Principal Balance	$ 0	$ 485,000
Post- Modification Recorded Principal Balance	$ 0	$ 482,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Number of Contracts	7	2
Pre- Modification Recorded Principal Balance	$ 758,000	$ 46,000
Post- Modification Recorded Principal Balance	$ 757,000	$ 46,000

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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