Note 6 - Loans and the Allowance for Loan Losses - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Number of contracts	6	9
Pre-modification outstanding recorded investment	$ 5,201	$ 7,750
Post-modification outstanding recorded investment	$ 3,060	$ 5,931
Residential Portfolio Segment [Member] \| Real Estate Residential One- to Four-Family [Member]
Number of contracts	2	3
Pre-modification outstanding recorded investment	$ 703	$ 870
Post-modification outstanding recorded investment	$ 455	$ 608
Consumer Portfolio Segment [Member]
Number of contracts	4	6
Pre-modification outstanding recorded investment	$ 4,498	$ 6,880
Post-modification outstanding recorded investment	$ 2,605	$ 5,323

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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