Note 5 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Recorded investment, with no allowance recorded	$ 6,457	$ 7,570
Unpaid principal balance, with no allowance recorded	8,262	9,280
Recorded investment, with a related allowance recorded	9,329	4,847
Unpaid principal balance, with a related allowance recorded	10,050	4,847
Related allowance	473	657
Recorded investment	15,786	12,417
Unpaid principal balance	18,312	14,127
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	1,217	313
Unpaid principal balance, with no allowance recorded	1,303	375
Recorded investment, with a related allowance recorded	1,494	1,534
Unpaid principal balance, with a related allowance recorded	1,494	1,534
Related allowance	9	14
Recorded investment	2,711	1,847
Unpaid principal balance	2,797	1,909
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	4,548	7,149
Unpaid principal balance, with no allowance recorded	6,007	8,795
Recorded investment, with a related allowance recorded	7,092	2,259
Unpaid principal balance, with a related allowance recorded	7,811	2,259
Related allowance	221	41
Recorded investment	11,640	9,408
Unpaid principal balance	13,818	11,054
Construction, Land Acquisition and Development [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	76	82
Unpaid principal balance, with no allowance recorded	76	82
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0	0
Recorded investment	76	82
Unpaid principal balance	76	82
Commercial and Industrial [Member]
Recorded investment, with no allowance recorded	593	0
Unpaid principal balance, with no allowance recorded	850	0
Recorded investment, with a related allowance recorded	571	697
Unpaid principal balance, with a related allowance recorded	573	697
Related allowance	242	600
Recorded investment	1,164	697
Unpaid principal balance	1,423	697
Consumer Portfolio Segment [Member]
Recorded investment, with no allowance recorded	23	26
Unpaid principal balance, with no allowance recorded	26	28
Recorded investment, with a related allowance recorded	172	357
Unpaid principal balance, with a related allowance recorded	172	357
Related allowance	1	2
Recorded investment	195	383
Unpaid principal balance	198	385
State and Political Subdivisions [Member]
Recorded investment, with no allowance recorded	0	0
Unpaid principal balance, with no allowance recorded	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0	0
Recorded investment	0	0
Unpaid principal balance	$ 0	$ 0

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 14A
-Subparagraph (b)
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-Publisher FASB
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