Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	May 31, 2012
Commitments and Contingencies Disclosure [Line Items]
Potential income tax payment due for fiscal years 2003 through 2005	$ 69.3
Allowance for doubtful account receivable
Commitments and Contingencies Disclosure [Line Items]
Valuation allowance for account receivable sold	$ 10.1

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant