Note 6 - Allowance for Loan Losses and Credit Quality Information - Financial Effects of Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of Contracts	16	19
Pre- modification Outstanding Recorded Investment	$ 2,232	$ 1,286
Post- modification Outstanding Recorded Investment	$ 2,235	$ 1,221
Residential Portfolio Segment [Member]
Number of Contracts	2	3
Pre- modification Outstanding Recorded Investment	$ 217	$ 282
Post- modification Outstanding Recorded Investment	$ 220	$ 514
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Number of Contracts	1	0
Pre- modification Outstanding Recorded Investment	$ 54	$ 0
Post- modification Outstanding Recorded Investment	$ 54	$ 0
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Number of Contracts	2	0
Pre- modification Outstanding Recorded Investment	$ 1,518	$ 0
Post- modification Outstanding Recorded Investment	$ 1,518	$ 0
Consumer Portfolio Segment [Member]
Number of Contracts	10	15
Pre- modification Outstanding Recorded Investment	$ 373	$ 588
Post- modification Outstanding Recorded Investment	$ 373	$ 591
Commercial Portfolio Segment [Member]
Number of Contracts	1	1
Pre- modification Outstanding Recorded Investment	$ 70	$ 416
Post- modification Outstanding Recorded Investment	$ 70	$ 116

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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