Share-Based Compensation (Compensation Cost Recognized in Income Statement) (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Before-tax share-based compensation cost	$ 16.9	$ 16.8
Income tax benefit	(4.1)	(4.1)
After-tax share-based compensation cost	$ 12.8	$ 12.7

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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