Stock-Based Compensation - Schedule Of Summary Of Restricted Stock Unit Activity (Details)	12 Months Ended
Sep. 30, 2025 $ / shares shares
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance	$ 155.99
Weighted Average Grant Date Fair Value, Ending balance	$ 251.46
Performance Shares [Member] \| Two Thousand Fourteen Equity Incentive Plan [Member]
Outstanding Restricted Stock Units
Outstanding Stock Units, Beginning balance \| shares	213,776
Outstanding Stock Units, Units granted \| shares	120,235
Outstanding Stock Units, Units vested \| shares	(117,333)
Outstanding Stock Units, Units cancelled \| shares	(32,955)
Outstanding Stock Units, Ending balance \| shares	183,723
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance	$ 155.63
Weighted Average Grant Date Fair Value, Units granted	248.47
Weighted Average Grant Date Fair Value, Units vested	174.32
Weighted Average Grant Date Fair Value, Units cancelled	170.83
Weighted Average Grant Date Fair Value, Ending balance	$ 220.40
Restricted Stock Units (RSUs) [Member] \| Two Thousand Fourteen Equity Incentive Plan [Member]
Outstanding Restricted Stock Units
Outstanding Stock Units, Beginning balance \| shares	1,312,328
Outstanding Stock Units, Units granted \| shares	1,167,667
Outstanding Stock Units, Units vested \| shares	(1,058,085)
Outstanding Stock Units, Units cancelled \| shares	(224,382)
Outstanding Stock Units, Ending balance \| shares	1,197,528
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance	$ 158.22
Weighted Average Grant Date Fair Value, Units granted	255.09
Weighted Average Grant Date Fair Value, Units vested	174.19
Weighted Average Grant Date Fair Value, Units cancelled	181.40
Weighted Average Grant Date Fair Value, Ending balance	$ 234.22

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

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- Definition

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 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 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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- Definition

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.

+ References

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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- Definition

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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No definition available.

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- Definition

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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- Definition

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

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- Definition

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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