Note 5 - Loans - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Pre-modification outstanding recorded investment	$ 81	$ 1,127	$ 81	$ 1,298
Post-modification outstanding recorded investment	$ 61	$ 1,127	$ 61	$ 1,297
Number of Contracts	1	1	1	2
Commercial Portfolio Segment [Member]
Pre-modification outstanding recorded investment		$ 1,127		$ 1,127
Post-modification outstanding recorded investment		$ 1,127		$ 1,127
Number of Contracts		1		1
Residential Portfolio Segment [Member] \| Individual Tax Identification Number Loan [Member] \| Real Estate Loan [Member]
Pre-modification outstanding recorded investment	$ 81		$ 81	$ 171
Post-modification outstanding recorded investment	$ 61		$ 61	$ 170
Number of Contracts	1		1	1

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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