Accounts Receivable - Trade Accounts And Notes Receivable (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Accounts Receivable
Trade receivables	$ 398,794	$ 398,739
Other receivables	17,351	11,656
Allowance for expected credit losses	(3,308)	(2,861)
Other allowances	(2,712)	(2,280)
Trade accounts and notes receivable	$ 410,125	$ 405,254