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Income Taxes - Additional Information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Income Taxes [Line Items]    
Provision or benefit for income taxes $ 0 $ 0
Income Tax Contingency [Abstract]    
Valuation allowance 104,800,000  
Increase (decrease) in valuation allowance $ 1,900,000  
Net operating loss carryforwards, Expire date begin to expire in 2021 and 2028  
State tax credit carryforwards $ 5,500,000  
Cumulative change in ownership 50.00%  
Period of net operating loss and R&D tax credit carry forwards to offset future taxable income 3 years  
Liability for uncertain tax positions $ 0 $ 0
Period for material changes of liability for uncertain tax benefits 12 months  
Interest related to unrecognized tax benefits in interest expense and penalties $ 0  
Federal [Member]    
Income Tax Contingency [Abstract]    
Tax loss carryforwards 396,200,000  
Federal tax carry forward $ 6,400,000  
Federal tax credit carryforward, Expiration date begin to expire in 2021  
Net operating losses $ 33,600,000  
Federal [Member] | Maximum [Member]    
Income Tax Contingency [Abstract]    
Percentage of federal net operating losses used to offset of future taxable income 80.00%  
State [Member]    
Income Tax Contingency [Abstract]    
Tax loss carryforwards $ 173,700,000