XML 94 R67.htm IDEA: XBRL DOCUMENT v3.20.4
Income Taxes - Additional Information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Jan. 01, 2018
Income Taxes [Line Items]        
Effective tax rate (0.04%) (0.12%) (0.27%)  
Valuation allowance $ 121,859,000 $ 74,959,000 $ 44,900,000 $ 27,500,000
Interest accrued in relation to uncertain tax positions 0      
Penalties accrued in relation to uncertain tax positions 0      
Domestic Tax Authority        
Income Taxes [Line Items]        
Net operating loss carryforwards for tax purposes $ 462,100,000      
Operating loss carryforwards earliest expiration year 2034      
Operating loss carryforwards latest expiration year 2037      
Net operating loss carryforwards expiring in indefinite period for tax purposes $ 335,900,000      
Domestic Tax Authority | Tax Period Expire from 2034 through 2037        
Income Taxes [Line Items]        
Net operating loss carryforwards for tax purposes $ 126,200,000      
State and Local Jurisdiction        
Income Taxes [Line Items]        
Operating loss carryforwards earliest expiration year 2034      
Operating loss carryforwards latest expiration year 2040      
State and Local Jurisdiction | Tax Period Expire from 2034 through 2040        
Income Taxes [Line Items]        
Net operating loss carryforwards for tax purposes $ 78,700,000