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Income Taxes - Additional Information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Income Taxes [Line Items]        
Increase in valuation allowance $ 96,600,000 $ 30,200,000    
Maturity period for net operating loss carryovers 20 years      
U.S. federal net operating losses $ 211,900,000      
Unrecognized tax benefits 3,489,000 2,052,000 $ 1,260,000 $ 1,031,000
Uncertain tax positions 1,437,000 792,000 $ 229,000  
Accrued interest or penalties related to uncertain tax positions 0 $ 0    
Domestic Tax Authority [Member]        
Income Taxes [Line Items]        
U.S. federal net operating losses 192,500,000      
U.S. federal tax credits $ 18,800,000      
Tax credit carryforwards expiration year 2028      
Net operating loss expiration year 2028