Contingencies and Other Accrued Losses - Additional Information (Detail) (USD $)	3 Months Ended
	Aug. 31, 2013	May 31, 2013
Schedule Of Commitments And Contingencies [Line Items]
Accrued contingencies		$ 65,100,000
(Decrease) in contingent payment	(61,894,000)
Expected payment to resolve issues arising out of investigation and other related costs	$ 3,200,000