OTHER GAINS (LOSSES), NET - Additional Information (Detail) (USD $)	12 Months Ended
	Jul. 31, 2012	Jul. 31, 2011		Jul. 31, 2010	Jul. 31, 2009
Gain (Loss) on Investments [Line Items]
De recognition of accrued pricing liabilities	$ 11,811,000	$ 13,545,000	[1]	$ 0	$ 0
Foreign exchange gains (losses)	2,900,000	(4,000,000)		(1,000,000)	(1,600,000)
Gain on investments	9,000	187,000	[1]	425,000	3,956,000
Gain related to the sale of available-for-sale securities		100,000
Gain related to the distribution of proceeds from the acquisition		100,000
Loss on disposal of assets				300,000	300,000
write-off of an investment					1,000,000
H2gen Innovations Inc And M2e Power Inc [Member]
Gain (Loss) on Investments [Line Items]
Gains related to acquisition				300,000
Virtual Ink Inc [Member]
Gain (Loss) on Investments [Line Items]
Gains related to acquisition				100,000
Foodbuy Limited Liability Company[Member]
Gain (Loss) on Investments [Line Items]
Gains related to acquisition					2,600,000
Generations Network Incorporation [Member]
Gain (Loss) on Investments [Line Items]
Gains related to acquisition					900,000
Avamar Technologies Incorporation [Member]
Gain (Loss) on Investments [Line Items]
Gains related to acquisition					$ 500,000

[1] As Restated