Capitalization and Short-Term Borrowings - Schedule of Share-Based Compensation for Restricted Stock Units and Performance Shares (Details) - $ / shares	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Non-Performance Based Restricted Stock Units (RSUs)
Number of Restricted Stock Units
Outstanding, beginning of year (in shares)	438,193
Granted (in shares)	132,352	220,778	133,173
Vested (in shares)	(128,028)
Forfeited (in shares)	(13,270)
Outstanding, end of year (in shares)	429,247	438,193
Weighted Average Fair Value per Award
Outstanding, beginning of year (in dollars per share)	$ 46.70
Granted (in dollars per share)	58.64	$ 42.44	$ 58.10
Vested (in dollars per share)	49.14
Forfeited (in dollars per share)	50.78
Outstanding, end of year (in dollars per share)	$ 49.53	$ 46.70
Performance Shares
Number of Restricted Stock Units
Outstanding, beginning of year (in shares)	719,577
Granted (in shares)	239,042	361,729	202,259
Vested (in shares)	(108,799)
Forfeited (in shares)	(206,823)
Change in Units Based on Performance Achieved (in shares)	9,478
Outstanding, end of year (in shares)	652,475	719,577
Weighted Average Fair Value per Award
Outstanding, beginning of year (in dollars per share)	$ 54.69
Granted (in dollars per share)	55.43	$ 44.23	$ 64.28
Vested (in dollars per share)	56.98
Forfeited (in dollars per share)	61.05
Change in Units Based on Performance Achieved (in dollars per share)	53.47
Outstanding, end of year (in dollars per share)	$ 52.55	$ 54.69

Change In Units Based On Performance Achieved, Weighted Average Grant Date Fair Value

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Other increase (decrease) in number of shares reserved for issuance under non-option equity instrument agreements that is not separately disclosed.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-4

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