Note 2 - Stock-Based Compensation (Details) - Stock Option Activity (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Note 2 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Exercised	2,500	0
Stock Option Plan 1999 [Member]
Note 2 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Options outstanding shares	46,000
Options outstanding weighted average exercise price	$ 23.96
Options outstanding weighted average remaining contractual term	211 days
Options outstanding aggregate intrinsic value	$ 163
Exercisable at September 30, 2014	43,500
Exercisable at September 30, 2014	$ 24.02
Exercisable at September 30, 2014	211 days
Exercisable at September 30, 2014	$ 163
Exercised	2,500
Exercised	$ 23.00
Options outstanding shares	43,500
Options outstanding weighted average exercise price	$ 24.02

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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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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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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 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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Weighted average remaining contractual term for fully vested and expected to vest options that are 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 price at which option holders acquired shares when converting their stock options into shares.

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

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