Composition of Certain Financial Statement Captions - Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation and amortization	$ (68,149)	$ (77,453)
Property and equipment, net	43,018	38,465
Property and equipment
Property, Plant and Equipment [Line Items]
Property and equipment	88,171	99,408
Internal-use software
Property, Plant and Equipment [Line Items]
Property and equipment	$ 22,996	$ 16,510

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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.

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