Increase to federal R&D credits due to the Tax Increase Prevention Act of 2014.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Name Accounting Standards Codification

-Glossary Carryforwards

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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-Topic 740

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Amount of interest expense accrued for an underpayment of income taxes.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Paragraph 15A

-Subparagraph (b)

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Note 11 - Income Taxes (Details) (USD $)	12 Months Ended
Note 11 - Income Taxes (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 01, 2012	Apr. 30, 2011
Note 11 - Income Taxes (Details) [Line Items]
Deferred Tax Assets, Valuation Allowance	$ 19,051,000	$ 16,739,000
Operating Loss Carryforwards	24,500,000us-gaap_OperatingLossCarryforwards	33,200,000us-gaap_OperatingLossCarryforwards
Unrecognized Tax Benefits	16,406,000us-gaap_UnrecognizedTaxBenefits	14,922,000us-gaap_UnrecognizedTaxBenefits	13,081,000us-gaap_UnrecognizedTaxBenefits	12,204,000us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	4,800,000	5,000,000
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	500,000	800,000
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority					10,500,000
Domestic Tax Authority [Member] \| Exercised Stock Option [Member]
Note 11 - Income Taxes (Details) [Line Items]
Tax Credit Carryforward, Amount		4,000,000
Domestic Tax Authority [Member]
Note 11 - Income Taxes (Details) [Line Items]
Operating Loss Carryforwards	24,500,000
Tax Credit Carryforward, Amount		16,700,000
State and Local Jurisdiction [Member] \| Exercised Stock Option [Member]
Note 11 - Income Taxes (Details) [Line Items]
Tax Credit Carryforward, Amount		1,400,000
State and Local Jurisdiction [Member]
Note 11 - Income Taxes (Details) [Line Items]
Operating Loss Carryforwards	28,000,000
Tax Credit Carryforward, Amount		14,700,000
Increase In R & D Credits [Member]
Note 11 - Income Taxes (Details) [Line Items]
Federal R&D credit	$ 1,900,000