Loss Per Share - Schedule of outstanding shares of potentially dilutive securities (Detail) - shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Earnings Per Share [Line Items]
Excluded from the computation of diluted net loss per share attributable to common stockholders	46,738,762	152,965,701
Common stock options outstanding
Earnings Per Share [Line Items]
Excluded from the computation of diluted net loss per share attributable to common stockholders	34,574,029	32,654,446
Convertible redeemable preferred stock outstanding
Earnings Per Share [Line Items]
Excluded from the computation of diluted net loss per share attributable to common stockholders	0	119,382,162
Unvested restricted stock awards
Earnings Per Share [Line Items]
Excluded from the computation of diluted net loss per share attributable to common stockholders	239,766	929,093
Founder Shares [Member]
Earnings Per Share [Line Items]
Excluded from the computation of diluted net loss per share attributable to common stockholders	1,500,000	0
Warrants to purchase common stock
Earnings Per Share [Line Items]
Excluded from the computation of diluted net loss per share attributable to common stockholders	10,424,967	0