Note 2 - Stock-based Compensation (Details) - Stock Option Activity - Stock Option Plan 1999 [Member] - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Note 2 - Stock-based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at January 1, 2015	20,500
Outstanding at January 1, 2015	$ 23.00
Exercised	(5,500)	(2,500)
Exercised	$ 23.00
Outstanding September 30, 2015	15,000	20,500
Outstanding September 30, 2015	$ 23.00	$ 23.00
Outstanding September 30, 2015	39 days
Outstanding September 30, 2015	$ 122
Exercisable at September30, 2015	15,000
Exercisable at September30, 2015	$ 23.00
Exercisable at September30, 2015	39 days
Exercisable at September30, 2015	$ 122

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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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.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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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.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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