Note 3 - Loans and Allowance for Loan Losses - Loans Modified as Troubled Debt Restructurings (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)
Number of Contracts	13	10	16	27
Pre- Modification Recorded Principal Balance	$ 3,947,000	$ 464,000	$ 4,077,000	$ 11,329,000
Post- Modification Recorded Principal Balance	$ 3,945,000	$ 465,000	$ 4,073,000	$ 10,726,000
Commercial Portfolio Segment [Member]
Number of Contracts	9	2	10	16
Pre- Modification Recorded Principal Balance	$ 3,523,000	$ 6,000	$ 3,546,000	$ 10,806,000
Post- Modification Recorded Principal Balance	$ 3,523,000	$ 6,000	$ 3,545,000	$ 10,201,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Number of Contracts	8	2	9	8
Pre- Modification Recorded Principal Balance	$ 2,831,000	$ 6,000	$ 2,854,000	$ 6,545,000
Post- Modification Recorded Principal Balance	$ 2,831,000	$ 6,000	$ 2,853,000	$ 6,542,000
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	1	0	1	8
Pre- Modification Recorded Principal Balance	$ 692,000	$ 0	$ 692,000	$ 4,261,000
Post- Modification Recorded Principal Balance	$ 692,000	$ 0	$ 692,000	$ 3,659,000
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	0	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Retail Portfolio Segment [Member]
Number of Contracts	4	8	6	11
Pre- Modification Recorded Principal Balance	$ 424,000	$ 458,000	$ 531,000	$ 523,000
Post- Modification Recorded Principal Balance	$ 422,000	$ 459,000	$ 528,000	$ 525,000
Retail Portfolio Segment [Member] \| Home Equity and Other [Member]
Number of Contracts	3	7	4	10
Pre- Modification Recorded Principal Balance	$ 414,000	$ 438,000	$ 485,000	$ 503,000
Post- Modification Recorded Principal Balance	$ 412,000	$ 439,000	$ 482,000	$ 505,000
Retail Portfolio Segment [Member] \| One to Four Family Mortgages [Member]
Number of Contracts	1	1	2	1
Pre- Modification Recorded Principal Balance	$ 10,000	$ 20,000	$ 46,000	$ 20,000
Post- Modification Recorded Principal Balance	$ 10,000	$ 20,000	$ 46,000	$ 20,000

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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