Note 3 - Loans - Modified in a Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)
Number of contracts		1
Pre-modification		$ 91
Post-modification		$ 91
Real Estate Portfolio Segment [Member] \| Residential [Member]
Number of contracts		1
Pre-modification		$ 91
Post-modification		$ 91

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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