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.

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Unrecognized cost of unvested share-based compensation awards.

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

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

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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 by which the current fair value of the underlying stock exceeds the 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		9 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax stock-based compensation expense associated with stock options	$ 1.3	$ 2.2	$ 8.2	$ 8.3
Tax benefit associated with stock options	0.4	0.7	2.7	2.7
Weighted average fair value for options granted, per share			$ 9.94	$ 11.51
Total intrinsic value of options exercised			17.1	19.8
Aggregate intrinsic value of options outstanding	64.6		64.6
Aggregate intrinsic value of options exercisable	63.6		63.6
Annual dividend yield			1.60%
2010 Master Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested stock options granted	$ 9.1		$ 9.1
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable from date of the grant, in years			1 year
Expected volatility			18.60%
Risk-free interest rate			0.05%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable from date of the grant, in years			8 years
Expected volatility			26.70%
Risk-free interest rate			2.27%