Note 3 - Loans and Allowance for Credit Losses - Loans Modified as Troubled Debt Restructurings (Details)	3 Months Ended
Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)
Number of Contracts	2	3
Pre- Modification Recorded Principal Balance	$ 128,000	$ 130,000
Post- Modification Recorded Principal Balance	$ 128,000	$ 129,000
Commercial Portfolio Segment [Member]
Number of Contracts	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 23,000
Post- Modification Recorded Principal Balance	$ 0	$ 22,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Number of Contracts	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 23,000
Post- Modification Recorded Principal Balance	$ 0	$ 22,000
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	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0
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	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0
Retail Portfolio Segment [Member]
Number of Contracts	2	2
Pre- Modification Recorded Principal Balance	$ 128,000	$ 107,000
Post- Modification Recorded Principal Balance	$ 128,000	$ 107,000
Retail Portfolio Segment [Member] \| One to Four Family Mortgages [Member]
Number of Contracts	2	1
Pre- Modification Recorded Principal Balance	$ 128,000	$ 36,000
Post- Modification Recorded Principal Balance	$ 128,000	$ 36,000
Retail Portfolio Segment [Member] \| Other Consumer Loans [Member]
Number of Contracts	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 71,000
Post- Modification Recorded Principal Balance	$ 0	$ 71,000

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

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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