The maximum number of potential shares to be delivered in payment under performance share awards.

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- Definition

Percentage of target shares to be delivered in payment under performance share awards.

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- Definition

Shares to be delivered in payment under performance share awards that vest.

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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.

+ References

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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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 date when the equity-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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- Definition

Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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- Definition

Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 50

-Section 50

-Paragraph 1

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-Paragraph 64, 65

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

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-Topic 718

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-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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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.

+ References

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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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Share Based Compensation (Details Textuals) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2011 Year Sites	Sep. 30, 2010	Sep. 30, 2009	Sep. 30, 2008	Sep. 30, 2007
Share-Based Compensation (Textuals) [Abstract]
Share-based compensation expense	$ 39.5	$ 36.3	$ 27.8
Income tax benefit related to share-based compensation, Total	12.9	11.9	9.1
Unrecognized compensation cost related to share-based compensation awards, net of estimated forfeitures, Total	38.4
Weighted average period for recognition of total unrecognized compensation cost	1.7
Stock options expiration period	10 years after the grant date
Performance shares payout			345,432	43,767	10,618
Payout percentage of target number of shares under performance share awards			200.00%	42.00%	13.00%
Stock Option [Member]
Share-Based Compensation (Textuals) [Abstract]
Vesting period	3 years
Per share weighted average fair value of stock options granted	$ 21.39	$ 13.59	$ 7.75
Total intrinsic value of stock option exercised	157.3	49.7	7.4
Performance shares [Member]
Share-Based Compensation (Textuals) [Abstract]
Vesting period	3 years
Per share weighted average fair value of performance shares, restricted stock and restricted stock units granted	$ 87.00	$ 54.81	$ 31.82
Maximum potential shares to be delivered in payment under performance share awards	148,960	270,460
Restricted stock and restricted stock units [Member]
Share-Based Compensation (Textuals) [Abstract]
Vesting period	1-5 years
Per share weighted average fair value of performance shares, restricted stock and restricted stock units granted	$ 69.00	$ 43.76	$ 29.38
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value	$ 4.5	$ 5.3	$ 1.6
2008 Long Term Incentive Plan [Member]
Share-Based Compensation (Textuals) [Abstract]
Number of shares authorized	11,200,000
Number of shares available for grant	5,000,000
2003 Directors Stock Incentive Plan [Member]
Share-Based Compensation (Textuals) [Abstract]
Number of shares authorized	500,000
Number of shares available for grant	300,000