Composition of Certain Financial Statement Captions - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Sep. 30, 2025
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation and amortization	$ (49,418)	$ (45,572)
Total	79,623	67,713
Property and equipment
Property, Plant and Equipment [Line Items]
Property and equipment	64,633	66,134
Internal-use software
Property, Plant and Equipment [Line Items]
Property and equipment	$ 64,408	$ 47,151

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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