Note 3 - Loans and Allowance for Credit Losses - Loans Modified as Troubled Debt Restructurings (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Number of Contracts	3	3	8	18
Pre- Modification Recorded Principal Balance	$ 308,000	$ 279,000	$ 7,094,000	$ 4,333,000
Post- Modification Recorded Principal Balance	$ 308,000	$ 278,000	$ 7,093,000	$ 4,329,000
Commercial Portfolio Segment [Member]
Number of Contracts	1	3	3	12
Pre- Modification Recorded Principal Balance	$ 19,000	$ 279,000	$ 6,593,000	$ 3,802,000
Post- Modification Recorded Principal Balance	$ 19,000	$ 278,000	$ 6,593,000	$ 3,801,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Number of Contracts	1	2	3	10
Pre- Modification Recorded Principal Balance	$ 19,000	$ 186,000	$ 6,593,000	$ 3,017,000
Post- Modification Recorded Principal Balance	$ 19,000	$ 185,000	$ 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	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Commercial Portfolio Segment [Member] \| Real Estate Owner Occupied Loan [Member]
Number of Contracts	0	0	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 692,000
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 692,000
Commercial Portfolio Segment [Member] \| Real Estate Non Owner Occupied Loan [Member]
Number of Contracts	0	0	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Commercial Portfolio Segment [Member] \| Real Estate Multi Family and Residential Rental Loan [Member]
Number of Contracts	0	1	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 93,000	$ 0	$ 93,000
Post- Modification Recorded Principal Balance	$ 0	$ 93,000	$ 0	$ 93,000
Retail Portfolio Segment [Member]
Number of Contracts	2	0	5	6
Pre- Modification Recorded Principal Balance	$ 289,000	$ 0	$ 501,000	$ 531,000
Post- Modification Recorded Principal Balance	$ 289,000	$ 0	$ 500,000	$ 528,000
Retail Portfolio Segment [Member] \| One to Four Family Mortgages [Member]
Number of Contracts	2	0	5	2
Pre- Modification Recorded Principal Balance	$ 289,000	$ 0	$ 501,000	$ 46,000
Post- Modification Recorded Principal Balance	$ 289,000	$ 0	$ 500,000	$ 46,000
Retail Portfolio Segment [Member] \| Other Consumer Loans [Member]
Number of Contracts	0	0	0	4
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 485,000
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 482,000

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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