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Note 9 - Stock Option Plan (Details) - Stock Option Activity - Stock Option Plan 1999 [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Note 9 - Stock Option Plan (Details) - Stock Option Activity [Line Items]
Outstanding at January 1, 2015	20,500
Outstanding at January 1, 2015	$ 23.00
Exercised	(7,500)	(2,500)	0
Exercised	$ 23.00
Forfeited or expired	(13,000)
Forfeited or expired	$ 23.00
Outstanding at December 31, 2015	0	20,500
Outstanding at December 31, 2015	$ 0	$ 23.00
Outstanding at December 31, 2015	0 years
Outstanding at December 31, 2015	$ 0
Exercisable at December 31, 2015	0
Exercisable at December 31, 2015	$ 0
Exercisable at December 31, 2015	0 years
Exercisable at December 31, 2015	$ 0

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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.

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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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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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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