Note 9 - Income Taxes (Details) - Components of the Company's Deferred Tax Asset - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Components of the Company's Deferred Tax Asset [Abstract]
Net operating loss carry forwards	$ 71,557	$ 64,021
Compensation expense related to employee stock options	4,953	4,235
Subtotal	76,510	68,255
Valuation allowance	$ (76,510)	$ (68,255)

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

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-Publisher FASB
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee compensation.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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