Note 9 - Income Taxes (Details) - Components of the Company's Deferred Tax Asset (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Components of the Company's Deferred Tax Asset [Abstract]
Net operating loss carry forwards	$ 61,536	$ 53,423
Compensation expense related to employee stock options	4,235	3,310
Subtotal	65,771us-gaap_DeferredTaxAssetsGross	56,733us-gaap_DeferredTaxAssetsGross
Valuation allowance	$ (65,771)	$ (56,733)

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

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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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