Income Taxes Components of deferred tax asset/ liability (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components of Deferred Tax Assets and Liabilities [Abstract]
Net operating loss carry forwards	$ 72,058	$ 60,961
Tax credit carry forwards	26,571	26,869
Fixed and intangible assets	6,424	7,246
Capitalized research and development costs	58	58
Reserves and other cumulative temporary differences	15,535	19,380
Gross deferred income tax assets	120,646us-gaap_DeferredTaxAssetsGross	114,514us-gaap_DeferredTaxAssetsGross
Valuation allowance	(120,646)	(114,514)
Net deferred income tax assets	$ 0us-gaap_DeferredTaxAssetsNet	$ 0us-gaap_DeferredTaxAssetsNet
Percentage of deferred tax assets on which valuation allowance is created		100.00%	100.00%

Amount of deferred tax liability attributable to taxable temporary differences from Fixed and intangible assets

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Percentage of deferred tax assets on which valuation allowance is created

+ References

No definition available.

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Glossary Deferred Tax Asset

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Amount after 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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The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

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-Glossary Carryforwards

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from other reserves and accruals not separately disclosed.

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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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Amount of deferred tax liability attributable to taxable temporary differences from research and development costs.

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