Note 4 - Loans, Allowance for Loan Losses and Other Real Estate Owned - Troubled Debt Restructurings (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of Contracts	15	18
Pre-Modification Carrying Value	$ 11,855	$ 14,162
Financing Receivable, Modifications, Recorded Investment	9,089	12,081
Period-End Individual Impairment Allowance	$ 36	$ 43
Commercial Portfolio Segment [Member]
Number of Contracts	6	7
Pre-Modification Carrying Value	$ 2,377	$ 2,393
Financing Receivable, Modifications, Recorded Investment	978	1,085
Period-End Individual Impairment Allowance	$ 36	$ 43
Commercial Real Estate Portfolio Segment [Member]
Number of Contracts	8	10
Pre-Modification Carrying Value	$ 9,237	$ 11,528
Financing Receivable, Modifications, Recorded Investment	7,907	10,788
Period-End Individual Impairment Allowance		$ 0
Residential Portfolio Segment [Member]
Number of Contracts	1	1
Pre-Modification Carrying Value	$ 241	$ 241
Financing Receivable, Modifications, Recorded Investment	204	208
Period-End Individual Impairment Allowance		$ 0

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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