Note 3 - Loans and Allowance for Loan Losses - Loans Modified as Troubled Debt Restructurings (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Number of Contracts	3	12	18	34
Pre- Modification Recorded Principal Balance	$ 279,000	$ 784,000	$ 4,333,000	$ 11,074,000
Post- Modification Recorded Principal Balance	$ 278,000	$ 784,000	$ 4,329,000	$ 10,478,000
Commercial Portfolio Segment [Member]
Number of Contracts	3	5	12	17
Pre- Modification Recorded Principal Balance	$ 279,000	$ 634,000	$ 3,802,000	$ 10,564,000
Post- Modification Recorded Principal Balance	$ 278,000	$ 634,000	$ 3,801,000	$ 9,968,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Number of Contracts	2	2	10	8
Pre- Modification Recorded Principal Balance	$ 186,000	$ 7,000	$ 3,017,000	$ 6,485,000
Post- Modification Recorded Principal Balance	$ 185,000	$ 7,000	$ 3,016,000	$ 6,491,000
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	1	1	7
Pre- Modification Recorded Principal Balance	$ 0	$ 56,000	$ 692,000	$ 3,508,000
Post- Modification Recorded Principal Balance	$ 0	$ 56,000	$ 692,000	$ 2,906,000
Commercial Portfolio Segment [Member] \| Real Estate Non Owner Occupied Loan [Member]
Number of Contracts	0	2	0	2
Pre- Modification Recorded Principal Balance	$ 0	$ 571,000	$ 0	$ 571,000
Post- Modification Recorded Principal Balance	$ 0	$ 571,000	$ 0	$ 571,000
Commercial Portfolio Segment [Member] \| Real Estate Multi Family and Residential Rental Loan [Member]
Number of Contracts	1	0	1	0
Pre- Modification Recorded Principal Balance	$ 93,000	$ 0	$ 93,000	$ 0
Post- Modification Recorded Principal Balance	$ 93,000	$ 0	$ 93,000	$ 0
Retail Portfolio Segment [Member]
Number of Contracts	0	7	6	17
Pre- Modification Recorded Principal Balance	$ 0	$ 150,000	$ 531,000	$ 510,000
Post- Modification Recorded Principal Balance	$ 0	$ 150,000	$ 528,000	$ 510,000
Retail Portfolio Segment [Member] \| Home Equity and Other [Member]
Number of Contracts	0	5	4	14
Pre- Modification Recorded Principal Balance	$ 0	$ 82,000	$ 485,000	$ 422,000
Post- Modification Recorded Principal Balance	$ 0	$ 83,000	$ 482,000	$ 423,000
Retail Portfolio Segment [Member] \| One to Four Family Mortgages [Member]
Number of Contracts	0	2	2	3
Pre- Modification Recorded Principal Balance	$ 0	$ 68,000	$ 46,000	$ 88,000
Post- Modification Recorded Principal Balance	$ 0	$ 67,000	$ 46,000	$ 87,000

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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