Stock-Based Compensation - Schedule of Assumptions Used in Black-Scholes Option-Pricing Model to Determine Grant-date Fair Value of Stock Options Granted (Detail)			3 Months Ended		9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate (in percentage)			4.20%	3.30%	4.00%	2.40%
Expected term (in years)			6 years 1 month 6 days	6 years 1 month 6 days	6 years	6 years 1 month 6 days
Expected volatility (in percentage)			94.70%	95.70%	93.50%	94.80%
Expected dividend yield (in percentage)			0.00%	0.00%	0.00%	0.00%
Class C Warrant Liability
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate (in percentage)	4.60%	4.00%	4.60%
Expected term (in years)	4 years 2 months 12 days	4 years 10 months 24 days	5 years 1 month 9 days
Expected volatility (in percentage)	91.30%	101.70%	97.40%
Expected dividend yield (in percentage)	0.00%	0.00%	0.00%
Expected forfeiture rate (in percentage)			19.00%