Note 13 - Employee Benefits (Details) - Stock Option Activity (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Stock Option Activity [Abstract]
Outstanding, January 1	58,581	79,693
Outstanding, January 1	$ 28.38	$ 27.25
Exercised	(11,223)	(21,112)
Exercised	$ 30.45	$ 24.11
Forfeited	(907)
Forfeited	$ 27.35
Outstanding, December 31	46,451	58,581
Outstanding, December 31	$ 27.90	$ 28.38
Exercisable, December 31	46,451	58,581
Exercisable, December 31	$ 27.90	$ 28.38

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)

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Number of options outstanding, including both vested and non-vested options.

+ References

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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