Litigation and Other Contingencies (Details) (Veliz lawsuit, USD $) In Millions	12 Months Ended
May 31, 2010	Jul. 20, 2011	Dec. 17, 2010
Veliz lawsuit
Litigation and Other Contingencies
Pre-tax impact of settlement, net of insurance proceeds	$ 19.5
Accrued aggregate cash payment for settlement		$ 1.9	$ 22.8

The difference of unusual or infrequent items gross less applicable insurance premiums.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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
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Reference 4: 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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+ Details