Stockholders' Equity - Schedule of Common Stock Reserved for Issuance (Detail) - shares	Mar. 31, 2024	Mar. 31, 2023
Class Of Stock [Line Items]
Outstanding stock options (in shares)	70,739,770	68,050,752
Total shares of common stock reserved (in shares)	238,918,589	163,884,802
2021 Equity Incentive Plan
Class Of Stock [Line Items]
Remaining shares available for future issuance under Amended and Restated 2021 Incentive Equity Plan (in shares)	111,276,882	55,922,182
Employee Stock Purchase Plan
Class Of Stock [Line Items]
Remaining shares available for future issuance under Employee Stock Purchase Plan (in shares)	12,845,267	13,349,302
Restricted Stock Units
Class Of Stock [Line Items]
Outstanding restricted stock units (in shares)	44,056,670	26,562,566