Inventories (Details) - USD ($) $ in Thousands	Apr. 27, 2019	Apr. 28, 2018
Inventories
Raw materials	$ 90,359	$ 86,214
Work in process	13,728	12,254
Finished goods	114,478	109,183
FIFO inventories	218,565	207,651
Excess of FIFO over LIFO	(21,666)	(22,810)
Total inventories	$ 196,899	$ 184,841

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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 by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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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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