Share-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Jul. 31, 2021	Apr. 30, 2021
Number of Stock Options Outstanding
Balance at beginning of period (in shares)	38,487
Options granted (in shares)	2,159
Options exercised (in shares)	(1,693)
Options cancelled (in shares)	(331)
Balance at end of period (in shares)	38,622	38,487
Vested and exercisable at end of period (in shares)	13,634
Vested and expected to vest at end of period (in shares)	39,460
Weighted Average Exercise Price
Balance at beginning of period (in dollars per share)	$ 6.39
Options granted (in dollars per share)	59.28
Options exercised (in dollars per share)	2.99
Options cancelled (in dollars per share)	10.81
Balance at end of period (in dollars per share)	9.46	$ 6.39
Vested and exercisable at end of period (in dollars per share)	3.71
Vested and expected to vest at end of period (in dollars per share)	$ 9.36
Weighted Average Remaining Contractual Life (years)
Balance at beginning of period	7 years 10 months 24 days	7 years 11 months 23 days
Balance at end of period	7 years 10 months 24 days	7 years 11 months 23 days
Vested and exercisable at end of period	6 years 9 months
Vested and expected to vest at end of period	7 years 10 months 24 days
Aggregate Intrinsic Value
Balance at beginning of period	$ 1,579,329	$ 2,304,714
Balance at end of period	1,579,329	$ 2,304,714
Vested and exercisable at end of period	635,917
Vested and expected to vest at end of period	$ 1,617,305