Note 4 - Loans - Loans Modified as TDRs (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Number of contracts	2	1	15	1
Pre-modification outstanding recorded investments	$ 85	$ 95	$ 7,243	$ 95
Post-modification outstanding recorded investments	$ 104	$ 99	$ 7,262	$ 99
Residential Portfolio Segment [Member]
Number of contracts		1	1	1
Pre-modification outstanding recorded investments		$ 95	$ 63	$ 95
Post-modification outstanding recorded investments		$ 99	$ 63	$ 99
Commercial Real Estate Portfolio Segment [Member]
Number of contracts			8
Pre-modification outstanding recorded investments			$ 5,250
Post-modification outstanding recorded investments			$ 5,250
Construction, Land Acquisition and Development [Member]
Number of contracts	0	0	0	0
Pre-modification outstanding recorded investments	$ 0	$ 0	$ 0	$ 0
Post-modification outstanding recorded investments	$ 0	$ 0	$ 0	$ 0
Commercial and Industrial [Member]
Number of contracts			4
Pre-modification outstanding recorded investments			$ 1,845
Post-modification outstanding recorded investments			$ 1,845
Consumer Portfolio Segment [Member]
Number of contracts	2	0	2	0
Pre-modification outstanding recorded investments	$ 85	$ 0	$ 85	$ 0
Post-modification outstanding recorded investments	$ 104	$ 0	$ 104	$ 0
State and Political Subdivisions [Member]
Number of contracts	0	0	0	0
Pre-modification outstanding recorded investments	$ 0	$ 0	$ 0	$ 0
Post-modification outstanding recorded investments	$ 0	$ 0	$ 0	$ 0

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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