Redeemable Convertible Preferred Stock and Redeemable Convertible A-1 Common Stock - Stock Outstanding (Details) - USD ($) $ in Thousands	Apr. 30, 2021	Nov. 30, 2020	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Series A*
Temporary Equity [Line Items]
Shares, Authorized (in shares)			21,000,000
Shares, Outstanding (in shares)			3,499,992
Liquidation Amount			$ 7,000
Carrying Value			$ 7,000
Series B*
Temporary Equity [Line Items]
Shares, Authorized (in shares)			27,360,000
Shares, Outstanding (in shares)			4,559,999
Liquidation Amount			$ 9,120
Carrying Value			$ 9,120
Series B-1A*
Temporary Equity [Line Items]
Shares, Authorized (in shares)			14,583,945
Shares, Outstanding (in shares)			2,430,635
Liquidation Amount			$ 15,853
Carrying Value			$ 15,717
Series B-1B*
Temporary Equity [Line Items]
Shares, Authorized (in shares)			556,680
Shares, Outstanding (in shares)			92,769
Liquidation Amount			$ 1,210
Carrying Value			$ 1,210
Series C*
Temporary Equity [Line Items]
Shares, Authorized (in shares)			16,678,511
Shares, Outstanding (in shares)			2,779,738
Liquidation Amount			$ 19,014
Carrying Value			$ 18,980
Series D
Temporary Equity [Line Items]
Shares, Authorized (in shares)			73,670,824
Shares, Outstanding (in shares)			12,278,422
Liquidation Amount			$ 103,662
Carrying Value			$ 103,531
Series E
Temporary Equity [Line Items]
Shares, Authorized (in shares)			3,240,060
Shares, Outstanding (in shares)			540,003
Liquidation Amount			$ 11,803
Carrying Value			$ 11,756
Series F
Temporary Equity [Line Items]
Shares, Authorized (in shares)			42,701,251
Shares, Outstanding (in shares)			5,399,581
Liquidation Amount			$ 81,322
Carrying Value			$ 81,157
Series G
Temporary Equity [Line Items]
Shares, Authorized (in shares)			23,392,520
Shares, Outstanding (in shares)			3,893,701
Liquidation Amount			$ 77,194
Carrying Value			$ 76,900
Series H
Temporary Equity [Line Items]
Shares, Authorized (in shares)			9,923,588
Shares, Outstanding (in shares)			1,653,928
Liquidation Amount			$ 50,000
Carrying Value			$ 49,836
Class A-1 common stock
Temporary Equity [Line Items]
Shares, Authorized (in shares)	0	6,666,667	6,666,667
Shares, Outstanding (in shares)	0		6,666,665	6,667,000	6,667,000
Liquidation Amount			$ 18,800
Carrying Value	$ 0		$ 18,800	$ 18,800	$ 18,800
Redeemable Convertible Preferred Stock
Temporary Equity [Line Items]
Shares, Authorized (in shares)	0	233,107,379	233,107,379
Shares, Outstanding (in shares)	0		37,128,768	34,192,000	31,582,000
Liquidation Amount			$ 376,178
Carrying Value	$ 0		$ 375,207	$ 299,965	$ 248,471