Changes Recognized in Other Comprehensive Income, Postretirement Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
May 31, 2013	May 31, 2012
Postretirement Benefits, U.S. Plans
Changes in plan assets and benefit obligations recognized in other comprehensive income:
Prior service cost
Net loss (gain) arising during the year	(1,014)	754
Amounts recognized as a component of net periodic benefit cost:
Amortization or curtailment recognition of prior service credit (cost)	86	86
Amortization or settlement recognition of net gain (loss)	(16)	58
Total recognized in other comprehensive loss (income)	(944)	898
Postretirement Benefits, Non-U.S. Plans
Changes in plan assets and benefit obligations recognized in other comprehensive income:
Prior service cost
Net loss (gain) arising during the year	1,988	6,979
Effect of exchange rates on amounts included in AOCI	(9)	(409)
Amounts recognized as a component of net periodic benefit cost:
Amortization or settlement recognition of net gain (loss)	(470)	(72)
Total recognized in other comprehensive loss (income)	$ 1,509	$ 6,498

Net of tax amount of the benefit improvement costs resulting from a plan amendment that occurred that has not been recognized in net periodic benefit cost.

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+ Details

- Definition

Net of tax amount of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

+ References

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

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-Name Accounting Standards Codification

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

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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