Shareholders' Equity (Details 3) (Management, USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Management
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Nonqualified stock options to purchase Of Shares	2,000,000
Nonqualified stock options to purchase Of Shares Exercise Price	$ 30.21
Deferred Compensation Arrangement With Individual - Requisite Service Period	Each option will become exercisable over five years
Deferred Compensation Arrangement With Individual - Maximum Contractual Term	Each option will become fully vested, assuming continued service, on April 14, 2014, the fifth anniversary of the date of grant
Term for not granting cash salary or bonus compensation in excess of $ 1.00 per year	5Y
Percentage of total aggregate options vested on April 14, 2010	20.00%
Percentage of stock options which would get immediately vested on termination of executive	100.00%
Percentage of stock options which would get immediately vested on change of control	100.00%
The total compensation expense to be recognized per grant	$ 26.1
Recognized compensation expense	$ 10.2	$ 10.1	$ 3.0

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Represents the term for granting stock in excess of cash salary or bonus in excess of dollar one.

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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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The per share price that the individual must pay to acquire shares under the deferred compensation arrangement.

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The maximum term of the deferred compensation arrangement.

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The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

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The minimum period that the individual is required to perform services in order to be fully vested under the deferred compensation arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

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