Note 4 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Recorded investment, with no allowance recorded	$ 8,077	$ 7,570
Unpaid principal balance, with no allowance recorded	9,897	9,280
Recorded investment, with a related allowance recorded	5,395	4,847
Unpaid principal balance, with a related allowance recorded	5,395	4,847
Related Allowance	906	657
Recorded Investment	13,472	12,417
Unpaid principal balance	15,292	14,127
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	342	313
Unpaid principal balance, with no allowance recorded	407	375
Recorded investment, with a related allowance recorded	1,492	1,534
Unpaid principal balance, with a related allowance recorded	1,492	1,534
Related Allowance	13	14
Recorded Investment	1,834	1,847
Unpaid principal balance	1,899	1,909
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	7,401	7,149
Unpaid principal balance, with no allowance recorded	9,154	8,795
Recorded investment, with a related allowance recorded	2,230	2,259
Unpaid principal balance, with a related allowance recorded	2,230	2,259
Related Allowance	40	41
Recorded Investment	9,631	9,408
Unpaid principal balance	11,384	11,054
Construction, Land Acquisition and Development [Member] \| Real Estate Loan [Member]
Recorded investment, with no allowance recorded	81	82
Unpaid principal balance, with no allowance recorded	81	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	81	82
Unpaid principal balance	81	82
Commercial and Industrial [Member]
Recorded investment, with no allowance recorded	228
Unpaid principal balance, with no allowance recorded	228
Recorded investment, with a related allowance recorded	1,318	697
Unpaid principal balance, with a related allowance recorded	1,318	697
Related Allowance	851	600
Recorded Investment	1,546	697
Unpaid principal balance	1,546	697
Consumer Portfolio Segment [Member]
Recorded investment, with no allowance recorded	25	26
Unpaid principal balance, with no allowance recorded	27	28
Recorded investment, with a related allowance recorded	355	357
Unpaid principal balance, with a related allowance recorded	355	357
Related Allowance	2	2
Recorded Investment	380	383
Unpaid principal balance	382	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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