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Stock Based Compensation Awards [Abstract]

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Total Award Range

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

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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 number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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Stock-Based Compensation Plans Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022	Jan. 27, 2022
Share-based Payment Award [Line Items]
Matching contribution on Director Deferred Compensation	33.30%
Market-based performance shares
Restricted Stock Awards [Abstract]
Fair value of restricted stock awards vested	$ 31.7		$ 6.6
Nonvestsed restricted stock awards	458,551	494,105
Grant date value per share	$ 135.83	$ 120.69
Granted	154,904
Maximum
Restricted Stock Awards [Abstract]
Total Award Range	260.00%
Post Long-Term Incentive Plans
Share-based Payment Award [Line Items]
Share-based Compensation Arrangement , Maximum Award Vesting Period	10 years
Stock Based Compensation Awards [Abstract]
Stock-based Compensation Expense	$ 85.1	$ 77.8	66.4
Recognized deferred tax beneft	11.2	$ 10.5	$ 9.1
Compensation cost related to nonvested awards not yet recognized	$ 73.1
Awards not yet recognized. weighted average period to be recognized	1 year 3 months 18 days
2021 Long-Term Incentive Plan
Restricted Stock Awards [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				2,400,000