Note 4 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Recorded investment, with no allowance recorded	$ 7,610	$ 5,500
Unpaid principal balance, with no allowance recorded	9,328	5,679
Recorded investment, with a related allowance recorded	4,828	5,841
Unpaid principal balance, with a related allowance recorded	4,828	5,880
Related Allowance	679	773
Recorded Investment	12,438	11,341
Unpaid principal balance	14,156	11,559
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	410	190
Unpaid principal balance, with no allowance recorded	469	216
Recorded investment, with a related allowance recorded	1,453	1,712
Unpaid principal balance, with a related allowance recorded	1,453	1,751
Related Allowance	16	33
Recorded Investment	1,863	1,902
Unpaid principal balance	1,922	1,967
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	7,075	5,174
Unpaid principal balance, with no allowance recorded	8,698	5,295
Recorded investment, with a related allowance recorded	2,281	2,990
Unpaid principal balance, with a related allowance recorded	2,281	2,990
Related Allowance	61	138
Recorded Investment	9,356	8,164
Unpaid principal balance	10,979	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	15	21
Unpaid principal balance, with no allowance recorded	50	53
Recorded investment, with a related allowance recorded	736	774
Unpaid principal balance, with a related allowance recorded	736	774
Related Allowance	600	600
Recorded Investment	751	795
Unpaid principal balance	786	827
Consumer Portfolio Segment [Member]
Recorded investment, with no allowance recorded	27	30
Unpaid principal balance, with no allowance recorded	28	30
Recorded investment, with a related allowance recorded	358	365
Unpaid principal balance, with a related allowance recorded	358	365
Related Allowance	2	2
Recorded Investment	385	395
Unpaid principal balance	386	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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