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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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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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Inventories, net - Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012
Inventory Disclosure [Abstract]
Raw materials	$ 4,725				$ 3,922
Work in process	681				1,637
Finished goods	332,309				321,318
Inventory, net	$ 337,715	$ 379,684	$ 345,766	$ 403,883	$ 326,877	$ 377,679	$ 341,737	$ 400,910