Share-Based Compensation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Share-Based Compensation (Textual) [Abstract]
Pre-tax share-based compensation expense	$ 11.5	$ 11.5
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	195	953
Wtd. Avg. Share Fair Value (usd per share)	$ 55.47	$ 35.86
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	44	37
Wtd. Avg. Share Fair Value (usd per share)	$ 298.10	$ 265.04
Restricted stock and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	126	45
Wtd. Avg. Share Fair Value (usd per share)	$ 245.07	$ 193.70
Unrestricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	4	5
Wtd. Avg. Share Fair Value (usd per share)	$ 221.90	$ 162.29

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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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).

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

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-Publisher FASB
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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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