Income Taxes (Reconciliation of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Deferred tax assets: | ||
| Net operating loss carryforwards | $ 233,225 | $ 226,911 |
| Research and development credits | 49,179 | 45,853 |
| Accruals and reserves | 6,337 | 8,024 |
| Stock-based compensation | 9,717 | 16,219 |
| ASC842 Operating lease liability | 9,870 | 10,837 |
| Total deferred tax assets | 308,328 | 307,844 |
| Less: Valuation allowance | (300,505) | (298,658) |
| Total deferred tax assets: | 7,823 | 9,186 |
| Fixed assets | (786) | (1,425) |
| ASC842 Operating Lease right-of-use assets | (7,037) | (7,761) |
| Total deferred tax liabilities | (7,823) | (9,186) |
| Net deferred tax assets |
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- Definition Deferred Tax Assets, Operating Lease Liabilities No definition available.
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- Definition Deferred Tax Liabilities, Right-of-use Assets No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before allocation of valuation allowances, of deferred tax asset attributable to deductible differences from reserves and accruals, compensation and benefit costs, and other provisions, reserves, and allowances. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from tax deferred revenue or income classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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