Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Income Tax Disclosure [Abstract] | ||
| Capitalized engineering costs | $ 2,812 | $ 11,749 |
| Capitalized start-up costs | 17,881 | 7,489 |
| Compensation and benefits | 5,465 | 2,052 |
| Federal | 19,423 | 4,230 |
| State | 522 | 0 |
| Foreign | 1,694 | 0 |
| Other, net | 3,541 | 878 |
| Deferred tax assets | 51,338 | 26,398 |
| Less valuation allowance | (50,942) | (26,398) |
| Deferred tax assets, net of valuation allowance | 396 | 0 |
| Deferred tax liabilities | (396) | 0 |
| Net deferred tax assets | $ 0 | $ 0 |
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- Definition Deferred Tax Assets, Capitalized Engineering Costs No definition available.
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- Definition Deferred Tax Assets, Capitalized Start-Up Costs No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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/presentationRef
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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/2003/role/presentationRef
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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/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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/presentationRef
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- References No definition available.
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