Note 4 - 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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Impaired loans with no related allowance, interest income recognized	$ 265	$ 138	$ 481	$ 351
Impaired loans with no related allowance, average recorded investment	29,843	25,805	29,864	28,395
Impaired loans with a related allowance, interest income recognized	44	61	73	100
Impaired loans with a related allowance, average recorded investment	3,540	8,891	2,916	7,943
Total impaired loans, interest income recognized	309	199	554	451
Total impaired loans, average recorded investment	33,383	34,696	32,780	36,338
Commercial Portfolio Segment [Member] \| Construction, Development and Other Land [Member]
Impaired loans with no related allowance, interest income recognized	5	1	12	14
Impaired loans with no related allowance, average recorded investment	790	823	795	969
Impaired loans with a related allowance, interest income recognized
Impaired loans with a related allowance, average recorded investment
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Impaired loans with no related allowance, interest income recognized	2	2	5	3
Impaired loans with no related allowance, average recorded investment	149	237	383	411
Impaired loans with a related allowance, interest income recognized
Impaired loans with a related allowance, average recorded investment
Commercial Portfolio Segment [Member] \| Multi-family Residential [Member]
Impaired loans with no related allowance, interest income recognized	7		16	10
Impaired loans with no related allowance, average recorded investment	1,269	296	1,444	547
Commercial Portfolio Segment [Member] \| Single Family Non-owner Occupied [Member]
Impaired loans with no related allowance, interest income recognized	28	25	56	48
Impaired loans with no related allowance, average recorded investment	3,237	2,307	3,116	2,634
Impaired loans with a related allowance, interest income recognized				7
Impaired loans with a related allowance, average recorded investment				439
Commercial Portfolio Segment [Member] \| Non-farm, Non-residential [Member]
Impaired loans with no related allowance, interest income recognized	47		64	39
Impaired loans with no related allowance, average recorded investment	5,230	4,048	4,953	5,579
Impaired loans with a related allowance, interest income recognized	8		8
Impaired loans with a related allowance, average recorded investment	553	1,374	277	770
Commercial Portfolio Segment [Member] \| Agricultural [Member]
Impaired loans with no related allowance, interest income recognized			2
Impaired loans with no related allowance, average recorded investment	48	175	51	229
Commercial Portfolio Segment [Member] \| Farmland [Member]
Impaired loans with no related allowance, interest income recognized	10	6	26	15
Impaired loans with no related allowance, average recorded investment	1,438	1,336	1,444	887
Impaired loans with a related allowance, interest income recognized
Impaired loans with a related allowance, average recorded investment		409		407
Consumer Real Estate Portfolio Segment [Member] \| Home Equity Lines [Member]
Impaired loans with no related allowance, interest income recognized	7	10	14	17
Impaired loans with no related allowance, average recorded investment	1,484	1,837	1,446	1,822
Impaired loans with a related allowance, interest income recognized		2		2
Impaired loans with a related allowance, average recorded investment		68		70
Consumer Real Estate Portfolio Segment [Member] \| Single Family Owner Occupied [Member]
Impaired loans with no related allowance, interest income recognized	154	86	278	193
Impaired loans with no related allowance, average recorded investment	15,838	14,247	15,889	14,917
Impaired loans with a related allowance, interest income recognized	36	59	65	91
Impaired loans with a related allowance, average recorded investment	2,987	7,040	2,639	6,257
Consumer Real Estate Portfolio Segment [Member] \| Owner Occupied Construction [Member]
Impaired loans with no related allowance, interest income recognized	2	3	4	6
Impaired loans with no related allowance, average recorded investment	223	292	222	259
Impaired loans with a related allowance, interest income recognized
Impaired loans with a related allowance, average recorded investment
Consumer and Other Portfolio Segment [Member] \| Consumer Loans [Member]
Impaired loans with no related allowance, interest income recognized	3	5	4	6
Impaired loans with no related allowance, average recorded investment	$ 137	$ 207	$ 121	$ 141

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=118936363&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=118936363&loc=d3e5258-111524

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