Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Oct. 31, 2011	Oct. 31, 2010
Comprehensive Income/Stockholders' Equity [Abstract]
Net income	$ 32,732	$ 26,281
Unrealized gain (loss) on cash flow hedges	1,330	(725)
Prior service credit and amortization of (gain) loss on post-retirement medical plan	668	(63)
Foreign currency translation adjustments	(19,118)	30,095
Total comprehensive income	$ 15,612	$ 55,588

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 reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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+ Details

- Definition

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

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+ Details

- Definition

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

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The adjustment out of other comprehensive income for actuarial gains or losses recognized as a component of net periodic benefit cost during the period, after tax.

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- Definition

Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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