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Note 6 - Securities Sold Under Agreements to Repurchase (Details) - Securities Sold Under Agreement To Repurchase (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Securities Sold Under Agreement To Repurchase [Abstract]
Outstanding balance at end of period	$ 63,165,000	$ 69,305,000
Average interest rate at end of period	0.13%	0.12%
Average daily balance during the period	76,412,000	65,939,000
Average interest rate during the period	0.12%	0.12%
Maximum daily balance during the period	$ 91,303,000	$ 78,960,000

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- Definition

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 resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

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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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Weighted average interest rate of short-term debt outstanding.

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