Leases -Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2021
Cash paid for amounts included in the measurement of operating lease liabilities:
Cash payments included in the measurement of operating lease liabilities – operating cash flows	$ 5,250	$ 4,667	$ 4,031
Right-of-use assets obtained in exchange for lease obligations (including remeasurement of right-of-use assets and lease liabilities due to changes in the timing of receipt of lease incentives)	(5,589)	26,529	0
Right-of-use assets obtained in exchange for lease obligations arising from lease modifications	$ 3,093	$ 1,572	$ 0