Employee Benefit Plan - Additional Information (Details) - Savings Plan - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Defined contribution plan, percentage of employee's contributions matched by employer	50.00%
Defined contribution plan, percentage of employer contribution on employee's earnings	3.00%
Matching contributions by employer	$ 8.6	$ 7.8	$ 7.8

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.

No definition available.

Name:	us-gaap_DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration