Stock-Based Compensation - Summary of Information Pertaining to Stock Purchase Rights Granted under Employee Stock Purchase Plan (Detail)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	2.20%	1.30%
Expected volatility	72.40%	75.30%
Expected dividend yield	0.00%
Expected life (in years)	6 years 2 months 19 days	6 years 2 months 15 days
2018 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.30%	0.10%
Expected volatility	64.10%	66.90%
Expected life (in years)	6 months	6 months