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Income Taxes - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 22, 2017
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Income Taxes Disclosure [Line Items]        
Federal statutory income tax rate, percent     21.00% 34.00%
Percentage of net operating loss carryforwards     80.00%  
Tax cuts and jobs act of 2017 change in tax rate income tax expense benefit $ 0      
Valuation allowance   $ 40,221,000 $ 15,395,000  
Operating loss carryforwards, limitations on use   $14.0 million will begin to expire in 2036 and $113.0 million can be carried forward indefinitely.    
Operating loss carryforward expiration in two thousand thirty six   $ 14,000,000    
Operating loss carryforward indefinitely   113,000,000    
Uncertain tax positions   0    
Penalties and interest accrued   0    
Federal        
Income Taxes Disclosure [Line Items]        
Operating loss carryforwards   $ 127,000,000    
Operating loss carryforwards, expiration date   Dec. 31, 2036    
Federal | Research Credits        
Income Taxes Disclosure [Line Items]        
Tax credit carryforward, amount   $ 3,800,000 900,000  
Tax credit carryforward, expiration date   Dec. 31, 2037    
State        
Income Taxes Disclosure [Line Items]        
Operating loss carryforwards   $ 130,800,000    
Operating loss carryforwards, expiration date   Dec. 31, 2036    
State | Research Credits        
Income Taxes Disclosure [Line Items]        
Tax credit carryforward, amount   $ 500,000 $ 200,000  
Tax credit carryforward, expiration date   Dec. 31, 2032