v2.4.0.6

Total Stock Based Compensation Expense (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 31, 2012	Aug. 31, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Accelerated stock option expense	$ 4	$ 4

X

- Details

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X

- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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