Note 4 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Recorded investment, with no allowance recorded	$ 6,496	$ 5,500
Unpaid principal balance, with no allowance recorded	7,464	5,679
Recorded investment, with a related allowance recorded	5,033	5,841
Unpaid principal balance, with a related allowance recorded	5,033	5,880
Related Allowance	696	773
Recorded Investment	11,529	11,341
Unpaid principal balance	12,497	11,559
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	205	190
Unpaid principal balance, with no allowance recorded	277	216
Recorded investment, with a related allowance recorded	1,596	1,712
Unpaid principal balance, with a related allowance recorded	1,596	1,751
Related Allowance	8	33
Recorded Investment	1,801	1,902
Unpaid principal balance	1,873	1,967
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	6,160	5,174
Unpaid principal balance, with no allowance recorded	7,023	5,295
Recorded investment, with a related allowance recorded	2,304	2,990
Unpaid principal balance, with a related allowance recorded	2,304	2,990
Related Allowance	86	138
Recorded Investment	8,464	8,164
Unpaid principal balance	9,327	8,285
Construction, Land Acquisition and Development [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	83	85
Unpaid principal balance, with no allowance recorded	83	85
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	83	85
Unpaid principal balance	83	85
Commercial and Industrial [Member]
Recorded investment, with no allowance recorded	20	21
Unpaid principal balance, with no allowance recorded	52	53
Recorded investment, with a related allowance recorded	773	774
Unpaid principal balance, with a related allowance recorded	773	774
Related Allowance	600	600
Recorded Investment	793	795
Unpaid principal balance	825	827
Consumer Portfolio Segment [Member]
Recorded investment, with no allowance recorded	28	30
Unpaid principal balance, with no allowance recorded	29	30
Recorded investment, with a related allowance recorded	360	365
Unpaid principal balance, with a related allowance recorded	360	365
Related Allowance	2	2
Recorded Investment	388	395
Unpaid principal balance	389	395
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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