Capitalization and Short-Term Borrowings - Schedule of Share-Based Compensation for Restricted Stock Units and Performance Shares (Details) - $ / shares	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Non-Performance Based Restricted Stock Units (RSUs)
Number of Restricted Stock Units
Outstanding, beginning of year (in shares)	342,186
Granted (in shares)	220,778	133,173	128,950
Vested (in shares)	(115,337)
Forfeited (in shares)	(9,434)
Outstanding, end of year (in shares)	438,193	342,186
Weighted Average Fair Value per Award
Outstanding, beginning of year (in dollars per share)	$ 49.63
Granted (in dollars per share)	42.44	$ 58.10	$ 54.10
Vested (in dollars per share)	46.92
Forfeited (in dollars per share)	50.43
Outstanding, end of year (in dollars per share)	$ 46.70	$ 49.63
Performance Shares
Number of Restricted Stock Units
Outstanding, beginning of year (in shares)	586,791
Granted (in shares)	361,729	202,259	195,397
Vested (in shares)	(251,255)
Forfeited (in shares)	(35,357)
Change in Units Based on Performance Achieved (in shares)	57,669
Outstanding, end of year (in shares)	719,577	586,791
Weighted Average Fair Value per Award
Outstanding, beginning of year (in dollars per share)	$ 55.46
Granted (in dollars per share)	44.23	$ 64.28	$ 65.39
Vested (in dollars per share)	38.62
Forfeited (in dollars per share)	46.49
Change in Units Based on Performance Achieved (in dollars per share)	37.36
Outstanding, end of year (in dollars per share)	$ 54.69	$ 55.46

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
-SubTopic 10
-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

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

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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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