Stockholders' Equity - Schedule of Fair Value of Award Granted Using Black-Scholes Option Pricing Model (Detail) |
3 Months Ended | 9 Months Ended | ||
---|---|---|---|---|
Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2021 |
Sep. 30, 2020 |
|
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Expected life (years) | 6 years | |||
Risk-free interest rate | 0.40% | |||
Volatility | 84.00% | |||
Dividend rate | 0.00% | 0.00% | 0.00% | 0.00% |
Minimum [Member] | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Expected life (years) | 5 years 6 months | 5 years 6 months | ||
Risk-free interest rate | 0.60% | 0.40% | ||
Volatility | 91.00% | 64.00% | ||
Maximum [Member] | ||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||||
Expected life (years) | 6 years | 6 years | ||
Risk-free interest rate | 1.00% | 0.50% | ||
Volatility | 108.00% | 84.00% |