Note 9 - Securities Sold Under Agreements to Repurchase (Details) - Securities Sold Under Agreement To Repurchase (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Securities Sold Under Agreement To Repurchase [Abstract]
Outstanding balance at year-end	$ 167,569,000	$ 69,305,000
Weighted average interest rate at year-end	0.11%	0.12%
Average daily balance during the year	105,474,000	65,939,000
Weighted average interest rate during the year	0.12%	0.12%
Maximum daily balance during the year	$ 178,042,000	$ 78,960,000

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The average effective interest rate during the reporting period.

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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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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

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No definition available.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.

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No definition available.

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Weighted average interest rate of short-term debt outstanding.

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