Other Expense (Income), Net (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Aug. 31, 2013	Aug. 31, 2012
Component Of Other Expense Income Nonoperating [Line Items]
Royalty expense (income), net	$ 318	$ (294)
Loss on Kemrock conversion option		8,183
(Income) loss related to unconsolidated equity affiliates	(752)	31,533
Other expense (income), net	$ (434)	$ 39,422

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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Ancillary revenue earned during the period from the consideration paid to the entity for the use of its rights and property by another party. Examples include licensing the use of copyrighted materials and leasing the extraction of natural resources.

+ References

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