Share-Based Compensation - Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Weighted Average Grant Date Fair Value Per RSU
Compensation expense recorded upon vesting of awards	$ 8,242	$ 8,564	$ 31,195	$ 27,961
Restricted Stock
RSUs
Unvested, beginning balance (in shares)			478,611	509,171
Awarded (in shares)			222,533	381,995
Vested (in shares)			(81,785)	(59,295)
Forfeited (in shares)			(5,795)	(20,263)
Unvested, ending balance (in shares)	613,564	811,608	613,564	811,608
Weighted Average Grant Date Fair Value Per RSU
Outstanding, beginning balance (in dollars per share)			$ 70.36	$ 31.59
Awarded (in dollars per share)			113.42	78.61
Vested (in dollars per share)			115.01	47.82
Forfeited (in dollars per share)			107.57	30.50
Outstanding, ending balance (in dollars per share)	$ 79.20	$ 52.58	$ 79.20	$ 52.58
Aggregate grant date fair value of shares awarded	$ 25,240	$ 30,027	$ 25,240	$ 30,027
Compensation expense recorded upon vesting of awards			21,184	8,236
Unrecognized compensation expense at fiscal year-end	$ 28,720	$ 27,638	$ 28,720	$ 27,638
Weighted average recognition period remaining, in years			3 years 5 months 15 days	3 years 11 months 15 days

Share-Based Compensation Arrangement By Share-Based Payment Award Aggregate Grant Date Fair Value

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- Definition

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

+ References

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-Topic 718
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- Definition

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

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- Definition

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.

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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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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

Weighted-average contractual term remaining for equity-based award excluding option, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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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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