Share-Based Compensation (Summary of Stock Option Activity) (Details) shares in Thousands	12 Months Ended
Sep. 30, 2020 $ / shares shares
Shares
Outstanding, beginning (shares) \| shares	1,344
Exercised (shares) \| shares	(403)
Forfeited (shares) \| shares	0
Outstanding, ending (shares) \| shares	941
Exercisable (shares) \| shares	941
Weighted Average Exercise Price
Outstanding, beginning (in dollars per share) \| $ / shares	$ 93.75
Exercised (in dollars per share) \| $ / shares	86.28
Forfeited (in dollars per share) \| $ / shares	0
Outstanding, ending (in dollars per share) \| $ / shares	96.95
Exercisable (in dollars per share) \| $ / shares	$ 96.95

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

Number of share options (or share units) exercised during the current period.

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