Net Loss per Share Attributable to Common Stockholders - Common Stock Equivalents Excluded from Calculation of Diluted Net Loss Per Share (Details) - Common Stock Class A - shares	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share Basic [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (n shares)	130,474,347	108,587,430	90,038,538
ESPP
Earnings Per Share Basic [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (n shares)	2,561,500	2,937,194	2,239,756
Outstanding stock options
Earnings Per Share Basic [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (n shares)	70,739,770	68,050,752	73,609,565
Unvested restricted stock units
Earnings Per Share Basic [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (n shares)	44,056,670	26,562,566	10,676,378
Shares subject to vesting
Earnings Per Share Basic [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (n shares)	0	2,576,082	3,512,839
2022 AIP RSUs
Earnings Per Share Basic [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share (n shares)	13,116,407	8,460,836	0