Note 6 - Loans and the Allowance for Loan Losses - Summary of Informative Data Regarding Loan Modifications (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Pre-Modification Outstanding Recorded Investment	$ 6,014	$ 7,750
Post-Modification Outstanding Recorded Investment	$ 4,582	$ 5,931
Number of Contracts	6	9
Residential Portfolio Segment [Member] \| Real Estate Residential One- to Four-Family [Member]
Pre-Modification Outstanding Recorded Investment	$ 870	$ 870
Post-Modification Outstanding Recorded Investment	$ 591	$ 608
Number of Contracts	3	3
Commercial Portfolio Segment [Member]
Pre-Modification Outstanding Recorded Investment	$ 5,144	$ 6,880
Post-Modification Outstanding Recorded Investment	$ 3,991	$ 5,323
Number of Contracts	3	6

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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