Note 3 - Loans and Allowance for Loan Losses - Summary of Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018 USD ($)	Jun. 30, 2017
Number of contracts	0	0	1	0
Pre-modification outstanding balance			$ 179
Post-modification outstanding balance			$ 179
Commercial Portfolio Segment [Member]
Number of contracts			1
Pre-modification outstanding balance			$ 179
Post-modification outstanding balance			$ 179

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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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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