Note 5 - Credit Quality - Average Annual Recorded Investment and Interest Income Recognized on Impaired Loans Excluding Purchased Credit Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Impaired loans with no related allowance, interest income recognized	$ 363	$ 265	$ 698	$ 481
Impaired loans with no related allowance, average recorded investment	40,622	29,843	37,460	29,864
Impaired loans with a related allowance, interest income recognized	25	44	38	73
Impaired loans with a related allowance, average recorded investment	4,605	3,540	4,062	2,916
Total impaired loans, average recorded investment	388	309	736	554
Total impaired loans, average recorded investment	45,227	33,383	41,522	32,780
Commercial Portfolio Segment [Member] \| Construction, Development and Other Land [Member]
Impaired loans with no related allowance, interest income recognized	7	5	15	12
Impaired loans with no related allowance, average recorded investment	882	790	1,091	795
Impaired loans with a related allowance, interest income recognized	0	0	0	0
Impaired loans with a related allowance, average recorded investment	0	0	0	0
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Impaired loans with no related allowance, interest income recognized	60	2	89	5
Impaired loans with no related allowance, average recorded investment	3,191	149	2,610	383
Impaired loans with a related allowance, interest income recognized	0	0	0	0
Impaired loans with a related allowance, average recorded investment	0	0	0	0
Commercial Portfolio Segment [Member] \| Multi-family Residential [Member]
Impaired loans with no related allowance, interest income recognized	18	7	29	16
Impaired loans with no related allowance, average recorded investment	417	1,269	544	1,444
Impaired loans with a related allowance, interest income recognized	0	0	0	0
Impaired loans with a related allowance, average recorded investment	944	0	943	0
Commercial Portfolio Segment [Member] \| Single Family Non-owner Occupied [Member]
Impaired loans with no related allowance, interest income recognized	37	28	72	56
Impaired loans with no related allowance, average recorded investment	5,203	3,237	4,652	3,116
Impaired loans with a related allowance, interest income recognized	0	0	0	0
Impaired loans with a related allowance, average recorded investment	0	0	0	0
Commercial Portfolio Segment [Member] \| Non-farm, Non-residential [Member]
Impaired loans with no related allowance, interest income recognized	84	47	127	64
Impaired loans with no related allowance, average recorded investment	8,886	5,230	6,780	4,953
Impaired loans with a related allowance, interest income recognized	14	8	14	8
Impaired loans with a related allowance, average recorded investment	1,884	553	1,611	277
Commercial Portfolio Segment [Member] \| Agricultural [Member]
Impaired loans with no related allowance, interest income recognized	2	0	3	2
Impaired loans with no related allowance, average recorded investment	264	48	235	51
Commercial Portfolio Segment [Member] \| Farmland [Member]
Impaired loans with no related allowance, interest income recognized	15	10	36	26
Impaired loans with no related allowance, average recorded investment	1,835	1,438	1,698	1,444
Impaired loans with a related allowance, interest income recognized	0	0	0	0
Impaired loans with a related allowance, average recorded investment	0	0	0	0
Consumer Real Estate Portfolio Segment [Member] \| Home Equity Lines [Member]
Impaired loans with no related allowance, interest income recognized	7	7	16	14
Impaired loans with no related allowance, average recorded investment	1,652	1,484	1,560	1,446
Impaired loans with a related allowance, interest income recognized	0	0	0	0
Impaired loans with a related allowance, average recorded investment	0	0	0	0
Consumer Real Estate Portfolio Segment [Member] \| Single Family Owner Occupied [Member]
Impaired loans with no related allowance, interest income recognized	122	154	290	278
Impaired loans with no related allowance, average recorded investment	17,251	15,838	17,401	15,889
Impaired loans with a related allowance, interest income recognized	11	36	24	65
Impaired loans with a related allowance, average recorded investment	1,777	2,987	1,508	2,639
Consumer Real Estate Portfolio Segment [Member] \| Owner Occupied Construction [Member]
Impaired loans with no related allowance, interest income recognized	4	2	10	4
Impaired loans with no related allowance, average recorded investment	534	223	434	222
Impaired loans with a related allowance, interest income recognized	0	0	0	0
Impaired loans with a related allowance, average recorded investment	0	0	0	0
Consumer and Other Portfolio Segment [Member] \| Consumer Loans [Member]
Impaired loans with no related allowance, interest income recognized	7	3	11	4
Impaired loans with no related allowance, average recorded investment	$ 507	$ 137	$ 455	$ 121

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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