Note 5 - Loans - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Number of contracts	0	1	8
Pre-modification outstanding recorded investment		$ 81	$ 2,760
Post-modification outstanding recorded investment		$ 61	$ 2,752
Commercial Portfolio Segment [Member]
Number of contracts			4
Pre-modification outstanding recorded investment			$ 2,244
Post-modification outstanding recorded investment			$ 2,266
Residential Portfolio Segment [Member] \| Individual Tax Identification Number Loan [Member] \| Real Estate Loan [Member]
Number of contracts		1	3
Pre-modification outstanding recorded investment		$ 81	$ 372
Post-modification outstanding recorded investment		$ 61	$ 342
Residential Portfolio Segment [Member] \| Residential One to Four Family [Member] \| Real Estate Loan [Member]
Number of contracts			1
Pre-modification outstanding recorded investment			$ 144
Post-modification outstanding recorded investment			$ 144

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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