Leases - Schedule of Assets and Liabilities Related to Operating and Financing Leases (Detail) - USD ($) $ in Thousands	Apr. 30, 2022	Apr. 30, 2021
Operating Leases
Right-of-use assets	$ 7,180
Accumulated amortization	(3,645)
Right-of-use assets, net	$ 3,535
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other assets
Current liabilities	$ 1,495	$ 1,309
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses and deferred revenue	Accrued expenses and deferred revenue
Non-current liabilities	$ 2,304
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other non-current liabilities
Total operating lease liabilities	$ 3,799
Finance Leases
Right-of-use assets	40,986	$ 40,986
Accumulated depreciation	(6,333)
Right-of-use assets, net	$ 34,653
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property, plant, and equipment, net
Current liabilities	$ 1,158	$ 1,087
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses and deferred revenue	Accrued expenses and deferred revenue
Non-current liabilities	$ 37,628	$ 38,786
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Non-current liabilities
Total finance lease liabilities	$ 38,786