Note 3 - Loans and Allowance for Loan Losses - Loans Modified as Troubled Debt Restructurings (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)
Number of Contracts	10	11	27	20
Pre- Modification Recorded Principal Balance	$ 464,000	$ 15,822,000	$ 11,329,000	$ 17,003,000
Post- Modification Recorded Principal Balance	$ 465,000	$ 16,120,000	$ 10,726,000	$ 17,290,000
Commercial Portfolio Segment [Member]
Number of Contracts	2	4	16	8
Pre- Modification Recorded Principal Balance	$ 6,000	$ 15,607,000	$ 10,806,000	$ 16,686,000
Post- Modification Recorded Principal Balance	$ 6,000	$ 15,904,000	$ 10,201,000	$ 16,972,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Number of Contracts	2	3	8	6
Pre- Modification Recorded Principal Balance	$ 6,000	$ 14,040,000	$ 6,545,000	$ 14,429,000
Post- Modification Recorded Principal Balance	$ 6,000	$ 14,337,000	$ 6,542,000	$ 14,726,000
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	8	2
Pre- Modification Recorded Principal Balance	$ 0	$ 1,567,000	$ 4,261,000	$ 2,257,000
Post- Modification Recorded Principal Balance	$ 0	$ 1,567,000	$ 3,659,000	$ 2,246,000
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	8	7	11	12
Pre- Modification Recorded Principal Balance	$ 458,000	$ 215,000	$ 523,000	$ 317,000
Post- Modification Recorded Principal Balance	$ 459,000	$ 216,000	$ 525,000	$ 318,000
Retail Portfolio Segment [Member] \| Home Equity and Other [Member]
Number of Contracts	7	4	10	8
Pre- Modification Recorded Principal Balance	$ 438,000	$ 93,000	$ 503,000	$ 163,000
Post- Modification Recorded Principal Balance	$ 439,000	$ 94,000	$ 505,000	$ 164,000
Retail Portfolio Segment [Member] \| One to Four Family Mortgages [Member]
Number of Contracts	1	3	1	4
Pre- Modification Recorded Principal Balance	$ 20,000	$ 122,000	$ 20,000	$ 154,000
Post- Modification Recorded Principal Balance	$ 20,000	$ 122,000	$ 20,000	$ 154,000

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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