Schedule of Changes in Unrecognized Tax Benefit (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011
Schedule of Unrecognized Tax Benefits [Line Items]
Beginning balance	$ 33,900	$ 32,174	$ 31,039
Tax positions related to prior years: Additions	436	562	1,817
Tax positions related to prior years: Reductions	(113)	(284)	(1,062)
Tax positions related to current year: Additions	5,348	3,995	3,713
Settlements	(5,593)	(1,364)	(2,642)
Lapses in statute of limitations	(1,245)	(1,183)	(691)
Ending balance	$ 32,733	$ 33,900	$ 32,174

Gross Amount Of Unrecognized Tax Benefits Excluding Interest and Penalties Pertaining to Uncertain Tax Positions

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

+ References

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

-Publisher FASB

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+ References

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

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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