Significant Accounting Policies - Schedule of Inventory (Details) - USD ($) $ in Thousands	May 31, 2016	May 31, 2015
Accounting Policies [Abstract]
Raw materials	$ 17,794	$ 16,935
Work in process	14,731	17,079
Finished goods	216,837	192,197
Inventories, net	249,362	226,211
Inventory obsolescence reserve	$ 32,900	$ 30,700

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

+ References

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-Publisher FASB
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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.

+ References

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

+ References

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Amount of valuation reserve for inventory.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

+ References

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