Revenue - Deferred Revenue Balance (Details) - USD ($) $ in Thousands		Oct. 31, 2021	Apr. 30, 2021	Oct. 31, 2020	Apr. 30, 2020
Revenue from Contract with Customer [Abstract]
Deferred revenue, current	[1]	$ 71,901	$ 72,263
Deferred revenue, non-current		980	2,964
Total deferred revenue		$ 72,881	$ 75,227	$ 81,956	$ 60,295

[1] Including amounts from a related party of $17,516 and $7,697 as of October 31, 2021 and April 30, 2021, respectively.