Note 15 - Financial Instruments With Off-balance Sheet Risk (Details Textual) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Standby Letters of Credit [Member]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	$ 2.9	$ 4.1
Commitments to Extend Credit [Member]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	$ 220.0	$ 188.0

The face amount of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

No definition available.

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