Leases - Summary of Lease Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2022	Apr. 30, 2021
Lease, Cost [Abstract]
Operating lease costs	$ 1,743	$ 926
Short-term lease costs	14	13
Variable lease costs	169	149
Total lease costs	$ 1,926	$ 1,088