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Income Taxes - Additional Information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Income Tax Disclosure [Abstract]    
Provision for income taxes $ 0  
Net operating loss carryforwards 233,600,000  
Research and experimentation tax carryforwards $ 3,600,000  
Description of tax credit carryforward expiration expire beginning in 2026  
Valuation allowance, deferred tax asset, explanation of change Company does not believe it is more likely than not that it will realize the benefits of net deferred tax assets and, accordingly, has established a valuation allowance equal to 100% of net deferred tax assets.  
Percentage of valuation allowance equal to net deferred tax assets 100.00%  
Increase in valuation allowance $ 4,900,000 $ 7,000,000.0
Accrued interest related to uncertain tax positions $ 0 $ 0
Income tax examination details All years will remain open for examining by federal and state authorities for three and four years, respectively, from the date of utilization of any net operating loss carryforwards.