Contingencies and Other Accrued Losses - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Aug. 31, 2012	May 31, 2012
Schedule Of Commitments And Contingencies [Line Items]
Increase in long-term accrued product liability reserves	$ 26.6	$ 25.8
Accrual contingencies	$ 11.4

Amount of increase (decrease) in loss contingency liability.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration