Property and Equipment - Component of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2025	Sep. 30, 2024
Property, Plant and Equipment [Abstract]
Property and equipment	$ 280,417	$ 250,896
Less: accumulated depreciation and amortization	152,447	146,362
Property and equipment, net	$ 127,970	$ 104,534

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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Name:	us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant