Composition of Certain Financial Statement Captions - Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation and amortization	$ (77,453)	$ (88,001)
Property and equipment, net	38,465	10,966
Technology Equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	74,084	69,928
Office Equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	9,473	12,296
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	15,851	16,743
Software and Software Development Costs
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 16,510	$ 0

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.

+ References

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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.

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