Note 17. Income Taxes (Detail) - Interest Accrued on Unrecognized Tax Benefits (Included in Unrecognized Tax Benefits [Member], USD $) In Thousands, unless otherwise specified	May 31, 2012	May 31, 2011
Included in Unrecognized Tax Benefits [Member]
Interest included in the liability for unrecognized tax benefits above	$ 1,234	$ 901

Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid.

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

-Publisher SEC

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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