Note 4 - Stock-based Compensation (Details Textual)	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($) shares	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) shares	Sep. 30, 2015 USD ($)
Officer [Member] \| Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	30,000
Three Independent Members of the Board of Directors [Member] \| The 2011 Non-employee Director Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			12,000
Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	12,000		12,000
Number of Stock-based Compensation Plans in Effect	3		3
Allocated Share-based Compensation Expense \| $	$ 7,000	$ 5,000	$ 17,000	$ 13,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized \| $	$ 116,000		$ 116,000

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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

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