Note 3 - Loans and Allowance for Loan Losses - Loans Modified as Troubled Debt Restructurings (Details)	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Number of Contracts	45	36
Pre- Modification Recorded Principal Balance	$ 22,498,000	$ 2,796,000
Post- Modification Recorded Principal Balance	$ 23,298,000	$ 2,797,000
Commercial Portfolio Segment [Member]
Number of Contracts	23	8
Pre- Modification Recorded Principal Balance	$ 21,896,000	$ 2,191,000
Post- Modification Recorded Principal Balance	$ 22,698,000	$ 2,191,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Number of Contracts	13	5
Pre- Modification Recorded Principal Balance	$ 6,914,000	$ 435,000
Post- Modification Recorded Principal Balance	$ 7,717,000	$ 435,000
Commercial Portfolio Segment [Member] \| Vacant Land and Land Development and Residential Construction Loan [Member]
Number of Contracts	0	1
Pre- Modification Recorded Principal Balance	$ 0	$ 87,000
Post- Modification Recorded Principal Balance	$ 0	$ 87,000
Commercial Portfolio Segment [Member] \| Real Estate Owner Occupied Loan [Member]
Number of Contracts	8	2
Pre- Modification Recorded Principal Balance	$ 14,663,000	$ 1,669,000
Post- Modification Recorded Principal Balance	$ 14,663,000	$ 1,669,000
Commercial Portfolio Segment [Member] \| Real Estate Non Owner Occupied Loan [Member]
Number of Contracts	2	0
Pre- Modification Recorded Principal Balance	$ 319,000	$ 0
Post- Modification Recorded Principal Balance	$ 318,000	$ 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	22	28
Pre- Modification Recorded Principal Balance	$ 602,000	$ 605,000
Post- Modification Recorded Principal Balance	$ 600,000	$ 606,000
Retail Portfolio Segment [Member] \| Home Equity and Other [Member]
Number of Contracts	16	20
Pre- Modification Recorded Principal Balance	$ 451,000	$ 295,000
Post- Modification Recorded Principal Balance	$ 452,000	$ 296,000
Retail Portfolio Segment [Member] \| One to Four Family Mortgages [Member]
Number of Contracts	6	8
Pre- Modification Recorded Principal Balance	$ 151,000	$ 310,000
Post- Modification Recorded Principal Balance	$ 148,000	$ 310,000

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=121611835&loc=SL6953676-111524

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