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Note 9 - Securities Sold Under Agreements to Repurchase (Details) - Securities Sold Under Agreement to Repurchase - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Securities Sold Under Agreement to Repurchase [Abstract]
Outstanding balance at year-end	$ 154,771,000	$ 167,569,000
Weighted average interest rate at year-end	0.11%	0.11%
Average daily balance during the year	$ 146,826,000	$ 105,474,000
Weighted average interest rate during the year	0.11%	0.12%
Maximum daily balance during the year	$ 168,211,000	$ 178,042,000

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The average effective interest rate during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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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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-Glossary Repurchase Agreement Accounted for as a Collateralized Borrowing
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Weighted average interest rate of short-term debt outstanding.

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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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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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