Inventories, net (Details) - USD ($) $ in Thousands	Jul. 27, 2019	Apr. 30, 2019
Inventories, net
Raw materials	$ 16,600	$ 16,792
Work in process	20,836	19,162
Finished goods	27,029	25,926
Inventories, gross	64,465	61,880
Reserve for inventory excess and obsolescence	(8,129)	(7,824)
Inventories, net	$ 56,336	$ 54,056

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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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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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