Share-based Compensation - Awards Granted to Company Employees and Non-employee Directors Under the 2007 Equity Incentive Compensation Plan (Detail)	3 Months Ended
Dec. 31, 2020 $ / shares shares
Non-qualified stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares) \| shares	1,022,430
Weighted-Average Grant Date Fair Value (in dollars per share)	$ 39.51
Weighted-Average Exercise Price (in USD per share)	$ 207.57
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares) \| shares	2,108,933
Weighted-Average Grant Date Fair Value (in dollars per share)	$ 207.52
Performance-bases shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares) \| shares	432,714
Weighted-Average Grant Date Fair Value (in dollars per share)	$ 229.81

The number of grants made 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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

+ 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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

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