Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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- 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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No definition available.

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

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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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Share-Based Compensation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Share-Based Compensation (Textual) [Abstract]
Pre-tax share-based compensation expense	$ 10.8	$ 10.2	$ 21.8	$ 18.8
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			946	856
Wtd. Avg. Share Fair Value (usd per share)			$ 32.48	$ 35.51
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			57	40
Wtd. Avg. Share Fair Value (usd per share)			$ 155.04	$ 219.04
Restricted stock and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			41	34
Wtd. Avg. Share Fair Value (usd per share)			$ 171.03	$ 192.50
Unrestricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			6	7
Wtd. Avg. Share Fair Value (usd per share)			$ 183.02	$ 183.76