Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2013	Jul. 31, 2012
Schedule Of Deferred Tax Assets (Liabilities) [Line Items]
Net deferred tax asset (liability)	$ 24,261	$ 18,694
North America
Schedule Of Deferred Tax Assets (Liabilities) [Line Items]
North America current liabilities	2,216	3,601
North America non-current assets	29,928	22,279
Foreign
Schedule Of Deferred Tax Assets (Liabilities) [Line Items]
Foreign non-current liabilities	$ (7,883)	$ (7,186)

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

+ References

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Amount of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed within one year or operating cycle, if longer.

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Gross amount of noncurrent deferred tax liabilities, which result from applying the applicable tax rate to taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax.

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