Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Restructurings By Class (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	4	2	7	4
Pre-modification outstanding principal balance	$ 1,130	$ 33	$ 1,380	$ 3,041
Post-modification outstanding principal balance	$ 1,130	$ 35	$ 1,380	$ 3,043
Commercial Non Real Estate Segment [Member] \| Commercial and Industrial [Member]
Number of contracts	2	1	4	1
Pre-modification outstanding principal balance	$ 1,116	$ 28	$ 1,234	$ 28
Post-modification outstanding principal balance	$ 1,116	$ 30	$ 1,234	$ 30
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate, Owner Occupied [Member]
Number of contracts			1
Pre-modification outstanding principal balance			$ 132
Post-modification outstanding principal balance			$ 132
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Number of contracts				2
Pre-modification outstanding principal balance				$ 3,008
Post-modification outstanding principal balance				$ 3,008
Consumer Non Real Estate Portfolio Segment [Member] \| Automobile Loan [Member]
Number of contracts	2	1	2	1
Pre-modification outstanding principal balance	$ 14	$ 5	$ 14	$ 5
Post-modification outstanding principal balance	$ 14	$ 5	$ 14	$ 5

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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