Note 3 - Loans and Allowance for Loan Losses - Loans Modified as Troubled Debt Restructurings (Details)	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Number of Contracts	18	45
Pre- Modification Recorded Principal Balance	$ 4,333,000	$ 22,498,000
Post- Modification Recorded Principal Balance	$ 4,329,000	$ 23,298,000
Commercial Portfolio Segment [Member]
Number of Contracts	12	23
Pre- Modification Recorded Principal Balance	$ 3,802,000	$ 21,896,000
Post- Modification Recorded Principal Balance	$ 3,801,000	$ 22,698,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Number of Contracts	10	13
Pre- Modification Recorded Principal Balance	$ 3,017,000	$ 6,914,000
Post- Modification Recorded Principal Balance	$ 3,016,000	$ 7,717,000
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	1	8
Pre- Modification Recorded Principal Balance	$ 692,000	$ 14,663,000
Post- Modification Recorded Principal Balance	$ 692,000	$ 14,663,000
Commercial Portfolio Segment [Member] \| Real Estate Non Owner Occupied Loan [Member]
Number of Contracts	0	2
Pre- Modification Recorded Principal Balance	$ 0	$ 319,000
Post- Modification Recorded Principal Balance	$ 0	$ 318,000
Commercial Portfolio Segment [Member] \| Real Estate Multi Family and Residential Rental Loan [Member]
Number of Contracts	1	0
Pre- Modification Recorded Principal Balance	$ 93,000	$ 0
Post- Modification Recorded Principal Balance	$ 93,000	$ 0
Retail Portfolio Segment [Member]
Number of Contracts	6	22
Pre- Modification Recorded Principal Balance	$ 531,000	$ 602,000
Post- Modification Recorded Principal Balance	$ 528,000	$ 600,000
Retail Portfolio Segment [Member] \| Home Equity and Other [Member]
Number of Contracts	4	16
Pre- Modification Recorded Principal Balance	$ 485,000	$ 451,000
Post- Modification Recorded Principal Balance	$ 482,000	$ 452,000
Retail Portfolio Segment [Member] \| One to Four Family Mortgages [Member]
Number of Contracts	2	6
Pre- Modification Recorded Principal Balance	$ 46,000	$ 151,000
Post- Modification Recorded Principal Balance	$ 46,000	$ 148,000

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 http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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