Annual report pursuant to Section 13 and 15(d)

Income Taxes -Schedule of Effective Income Tax Rate Reconciliation (Detail)

v3.20.1
Income Taxes -Schedule of Effective Income Tax Rate Reconciliation (Detail)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Income Tax Contingency [Line Items]    
Tax benefit at federal statutory rate (21.00%) (21.00%)
State income taxes (5.70%) (7.70%)
Permanent differences:    
Stock-based compensation 3.10% (2.20%)
Meals and entertainment 0.10% 0.10%
Executive compensation 1.00% 0.20%
Effective income tax rate 0.00% 0.00%
Domestic Tax Authority [Member]    
Permanent differences:    
Effective income tax rate reconciliation, prior year income taxes, percent (1.30%) 0.10%
Effective income tax rate reconciliation, tax credit, research, percent (2.10%) (1.90%)
Effective income tax rate reconciliation, change in deferred tax assets valuation allowance, percent 20.20% 24.70%
State and Local Jurisdiction [Member]    
Permanent differences:    
Effective income tax rate reconciliation, prior year income taxes, percent (0.10%)  
Effective income tax rate reconciliation, tax credit, research, percent (1.40%) (1.40%)
Effective income tax rate reconciliation, change in deferred tax assets valuation allowance, percent 7.20% 9.10%