Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Section 50

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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Accounting For Stock-Based Compensation (Narrative) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jan. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual dividend yield			1.00%
Weighted average fair value for options granted, per share			$ 8.33	$ 9.43
Pretax compensation expense associated with stock options	$ 4.1	$ 4.3	$ 5.5	$ 5.1
Tax benefit associated with stock options	1.4	1.5	1.8	1.7
Total intrinsic value of options exercised			24.5	22.3
Aggregate intrinsic value of options outstanding	110.2		110.2
Aggregate intrinsic value of options exercisable	102.4		102.4
Unrecognized compensation expense related to non-vested stock options granted	$ 10.2		$ 10.2
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)			8 years
Expected volatility			29.50%
Risk-free interest rate			1.57%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)			1 year
Expected volatility			23.40%
Risk-free interest rate			0.02%