Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands  | 
Dec. 31, 2016  | 
Dec. 31, 2015  | 
|---|---|---|
| Income Tax Disclosure [Abstract] | ||
| Net operating loss carryforwards | $ 20,633 | $ 14,273 | 
| Compensation | 1,323 | 1,098 | 
| Research and development tax credits | 1,390 | 972 | 
| Property and equipment | 22 | |
| Other | 545 | 128 | 
| Total gross deferred tax assets | 23,912 | 16,471 | 
| Property and equipment | (5) | |
| Acquired in-process research and development | (20,462) | (49,875) | 
| Total Deferred Tax Liabilities | (20,462) | (49,880) | 
| Net deferred tax assets | 3,450 | (33,409) | 
| Valuation allowance | (23,912) | (16,466) | 
| Net Deferred Tax Liability | $ (20,462) | $ (49,875) | 
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- Definition custom:AcquiredInprocessResearchAndDevelopment No definition available. 
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- Definition Carrying amount as of the balance sheet date of assets held under deferred compensation agreements. 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 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 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 loss carryforwards, 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 property, plant, and equipment. No definition available. 
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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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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from research and development costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- References No definition available. 
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