Note 5 - Loans - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Number of contracts	1	8	13
Pre-modification outstanding recorded investment	$ 81	$ 2,760	$ 2,109
Post-modification outstanding recorded investment	$ 61	$ 2,752	$ 1,895
Commercial Portfolio Segment [Member]
Number of contracts		4	2
Pre-modification outstanding recorded investment		$ 2,244	$ 872
Post-modification outstanding recorded investment		$ 2,266	$ 872
Residential Portfolio Segment [Member] \| Individual Tax Identification Number Loan [Member] \| Real Estate Loan [Member]
Number of contracts	1	3	11
Pre-modification outstanding recorded investment	$ 81	$ 372	$ 1,237
Post-modification outstanding recorded investment	$ 61	$ 342	$ 1,023

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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