Stock Option and Incentive Plan - Summary of Option Activity (Detail) shares in Thousands	12 Months Ended
Sep. 30, 2017 $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Share Options, Outstanding, Beginning Balance \| shares	7,623
Number of Share Options, Granted \| shares	2,062
Number of Share Options, Exercised \| shares	(2,220)
Number of Share Options, Forfeited \| shares	(508)
Number of Share Options, Outstanding, Ending Balance \| shares	6,957
Number of Share Options, Exercisable \| shares	2,428
Weighted Average Exercise Price, Outstanding, Beginning Balance \| $ / shares	$ 44.20
Weighted Average Exercise Price, Granted \| $ / shares	58.83
Weighted Average Exercise Price, Exercised \| $ / shares	39.63
Weighted Average Exercise Price, Forfeited \| $ / shares	50.60
Weighted Average Exercise Price, Outstanding, Ending Balance \| $ / shares	49.52
Weighted Average Exercise Price, Exercisable \| $ / shares	$ 40.33

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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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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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.

+ References

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Gross number of share options (or share units) granted during the period.

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

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

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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