Customer Receivables (Components Of Customer Receivables ) (Details) - USD ($) $ in Thousands	Jul. 31, 2021	Apr. 30, 2021
Accounts Receivable, after Allowance for Credit Loss [Abstract]
Gross customer receivables	$ 139,498	$ 156,187
Less:
Allowance for doubtful accounts	(220)	(331)
Allowance for returns and discounts	(8,542)	(8,990)
Net customer receivables	$ 130,736	$ 146,866

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Balance Type:	debit
Period Type:	instant