Inventories (Details) (USD $) In Thousands, unless otherwise specified	Apr. 26, 2014	Apr. 27, 2013
Inventories [Abstract]
Raw materials	$ 71,247	$ 70,731
Work in process	13,722	12,182
Finished goods	91,842	93,273
FIFO inventories	176,811	176,186
Excess of FIFO over LIFO	(29,802)	(29,843)
Inventories, net	$ 147,009	$ 146,343

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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 of difference between inventory at lower of LIFO cost or market and inventory at lower of other inventory accounting method cost or market, for example, but not limited to, FIFO or average cost.

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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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