Note 7 - Short-term Borrowings (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Short-term Debt, Total	$ 10,298	$ 15,594
Federal Funds Purchased	0	0
Available Fund Lines From Correspondent Banks	18,800	18,800
Securities Sold under Agreements to Repurchase, Total	300	600
Federal Home Loan Bank, Advances, Maturities Summary, Due in Next Twelve Months, Total	$ 10,000	$ 15,000
Minimum [Member]
Maturity Period of Federal Funds	1 day
Maximum [Member]
Maturity Period of Federal Funds	4 days

Available fund lines from correspondent banks.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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