Stock-Based Compensation Plans - Ranges of Underlying Assumptions Used in BSM Option Pricing Model to Determine Fair Value of Stock Options Granted to Employees and Nonemployees (Detail) - 2019 Omnibus Equity Incentive Plan	6 Months Ended
	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.06%
Expected dividend yield	0.00%
Expected volatility	84.40%
Expected term of options (years)	5 years 9 months 3 days