Net (Loss) Income Per Share Attributable to Common Stockholders - Potential Shares Excluded From Computation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Jul. 31, 2021	Jul. 31, 2020
Series A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	3,499,992
Series B
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	4,559,999
Series B-1A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	2,430,635
Series B-1B
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	92,769
Series C
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	2,779,738
Series D
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	12,278,422
Series E
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	540,003
Series F
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	5,399,581
Series G
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	3,893,701
Series H
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	0	1,653,928
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	39,433,289	32,859,250
RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially antidilutive shares excluded from computation of net loss per share (in shares)	3,897,893	0