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Share-Based Compensation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-Based Compensation (Textual) [Abstract]
Pre-tax share-based compensation expense	$ 13.5	$ 12.3	$ 37.9	$ 34.7
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)			196	973
Wtd. Avg. Share Fair Value (usd per share)			$ 55.50	$ 35.79
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)			181	67
Wtd. Avg. Share Fair Value (usd per share)			$ 248.16	$ 198.77
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)			$ 228.80	$ 171.51