Accrued Expenses and Deferred Revenue - Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Oct. 31, 2021	Apr. 30, 2021
Payables and Accruals [Abstract]
Accrued taxes other than income	$ 10,867	$ 12,210
Accrued distributor incentives	3,875	2,414
Accrued employee benefits	3,773	4,780
Accrued other	3,673	3,451
Accrued rebates and promotions	3,458	2,174
Accrued professional fees	3,161	2,804
Current portion of operating lease obligation	1,360	1,309
Current portion of finance lease obligation	1,116	1,087
Deferred revenue	675	2,907
Total accrued expenses and deferred revenue	$ 31,958	$ 33,136