Inventories (Components Of Inventories) (Details) - USD ($) $ in Thousands	Jul. 31, 2021	Apr. 30, 2021
Inventory, Net [Abstract]
Raw materials	$ 80,700	$ 63,384
Work-in-process	55,875	51,176
Finished goods	45,219	43,607
Inventories	$ 181,794	$ 158,167

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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