Quarterly report pursuant to Section 13 or 15(d)

Stock Plans - Schedule of Fair Value Assumptions (Detail)

v3.21.2
Stock Plans - Schedule of Fair Value Assumptions (Detail) - Stock Options [Member]
9 Months Ended
Sep. 30, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Expected volatility, minimum 80.00%
Expected volatility, maximum 83.00%
Risk-free interest rate, minimum 0.60%
Risk-free interest rate, maximum 1.00%
Minimum [Member]  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Expected term (in years) 5 years 6 months
Maximum [Member]  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Expected term (in years) 6 years 1 month 6 days