Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Oct. 31, 2011	Oct. 31, 2010
Comprehensive Income [Abstract]
Net income	$ 41,149	$ 37,823
Other comprehensive income:
Cash flow hedge	(614)
Foreign currency translation adjustments, net of tax effects	(3,500)	4,258
Comprehensive income	$ 37,035	$ 42,081

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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

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-Glossary Other Comprehensive Income

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Reference 12: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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+ Details

- Definition

Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity, net of tax.

+ References

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

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+ Details