Gross Unrecognized Tax Benefits (Detail) (USD $) In Millions, unless otherwise specified	Apr. 30, 2014	Jul. 31, 2013
Schedule of Unrecognized Tax Benefits [Line Items]
Gross unrecognized tax benefits	$ 6.6	$ 7.3

Gross Amount Of Unrecognized Tax Benefits Excluding Interest And Penalties Pertaining To Uncertain Tax Positions

No definition available.

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Period Type:	instant