v3.20.1
Income Taxes - Schedule of Reconciliation of Statutory Federal Income Tax (Detail)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Income Tax Disclosure [Abstract]    
Federal tax at statutory rate (21.00%) (21.00%)
State and local tax at statutory rates, net of federal income tax (0.82%) (4.15%)
Research and development credits (3.39%) (6.37%)
Other 0.56% 4.27%
Change in valuation allowance 24.65% 27.25%
Effective tax rate 0.00% 0.00%