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

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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, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Share-Based Compensation (Textual) [Abstract]
Pre-tax share-based compensation expense	$ 10.9	$ 10.8	$ 22.4	$ 21.8
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			970	946
Wtd. Avg. Share Fair Value (usd per share)			$ 35.78	$ 32.48
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			37	57
Wtd. Avg. Share Fair Value (usd per share)			$ 265.04	$ 155.04
Restricted stock and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			49	41
Wtd. Avg. Share Fair Value (usd per share)			$ 192.60	$ 171.03
Unrestricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			7	6
Wtd. Avg. Share Fair Value (usd per share)			$ 171.51	$ 183.02