Note 5 - Allowance for Loan Losses - Impaired Loans Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
With no related allowance recorded - Average recorded investment	$ 11,885	$ 16,703	$ 14,570
With no related allowance recorded - Interest income recognized	354	419	483
With related allowance - Average recorded investment	6,220	6,098	10,817
With related allowance - Interest income recognized	32	32	124
Average recorded investment	18,105	22,801	25,387
Interest income recognized	386	451	607
Commercial Real Estate Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	6,463	10,429	9,579
With no related allowance recorded - Interest income recognized	289	288	366
With related allowance - Average recorded investment	4,281	3,076	6,490
With related allowance - Interest income recognized	1		14
Average recorded investment	10,744	13,505	16,069
Interest income recognized	290	288	380
Construction and Land Development Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment
With no related allowance recorded - Interest income recognized
With related allowance - Average recorded investment
With related allowance - Interest income recognized
Average recorded investment
Interest income recognized
Commercial Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	2,144	3,341	2,270
With no related allowance recorded - Interest income recognized	5	52	37
With related allowance - Average recorded investment	838	1,862	2,517
With related allowance - Interest income recognized		6	68
Average recorded investment	2,982	5,203	4,787
Interest income recognized	5	58	105
Owner Occupied Real Estate [Member]
With no related allowance recorded - Average recorded investment	1,908	2,275	1,894
With no related allowance recorded - Interest income recognized	38	58	58
With related allowance - Average recorded investment	1,071	969	1,390
With related allowance - Interest income recognized	31	25	32
Average recorded investment	2,979	3,244	3,284
Interest income recognized	69	83	90
Consumer Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	909	658	801
With no related allowance recorded - Interest income recognized	20	21	21
With related allowance - Average recorded investment	30	191	420
With related allowance - Interest income recognized		1	10
Average recorded investment	939	849	1,221
Interest income recognized	20	22	31
Residential Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	461		26
With no related allowance recorded - Interest income recognized	2		1
With related allowance - Average recorded investment
With related allowance - Interest income recognized
Average recorded investment	461		26
Interest income recognized	$ 2		$ 1

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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+ References

Reference 1: 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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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 19
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