Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Restructurings By Class (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)	Mar. 31, 2017
Number of contracts	2	0
Pre-modification outstanding principal balance	$ 2,882
Post-modification outstanding principal balance	$ 2,882
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Number of contracts	2
Pre-modification outstanding principal balance	$ 2,882
Post-modification outstanding principal balance	$ 2,882

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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