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Note 3 - Loans and Allowance for Credit Losses - Nonperforming Loans (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Loans past due 90 days or more still accruing interest	$ 0	$ 0
Nonaccrual loans	7,782,000	7,728,000
Commercial Portfolio Segment [Member]
Loans past due 90 days or more still accruing interest	0	0
Nonaccrual loans	5,883,000	6,272,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans past due 90 days or more still accruing interest	0	0
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans past due 90 days or more still accruing interest	0	0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans past due 90 days or more still accruing interest	0	0
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans past due 90 days or more still accruing interest	0	0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans past due 90 days or more still accruing interest	0	0
Retail Portfolio Segment [Member]
Loans past due 90 days or more still accruing interest	0	0
Nonaccrual loans	1,899,000	1,456,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans past due 90 days or more still accruing interest	0	0
Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Loans past due 90 days or more still accruing interest	0	0
Nonperforming Financial Instruments [Member]
Loans past due 90 days or more still accruing interest	0	0
Nonaccrual loans	7,782,000	7,728,000
Total nonperforming loans	7,782,000	7,728,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Total nonperforming loans	5,883,000	6,272,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Total nonperforming loans	5,654,000	6,024,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Total nonperforming loans	0	0
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Total nonperforming loans	229,000	248,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Total nonperforming loans	0	0
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Total nonperforming loans	0	0
Nonperforming Financial Instruments [Member] | Retail Portfolio Segment [Member]
Total nonperforming loans	1,899,000	1,456,000
Nonperforming Financial Instruments [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Total nonperforming loans	1,899,000	1,456,000
Nonperforming Financial Instruments [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Total nonperforming loans	$ 0	$ 0

X

- Definition

Amount of financing receivables which are past due 90 days or more and still accruing interest and nonaccrual loans.

+ References

No definition available.

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- Definition

Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 80
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-80

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Paragraph 16
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 310
-Publisher FASB
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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
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