Leases - Schedule of Components of Lease Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Sep. 30, 2024
Lease Assets and Liabilities
Right-of-use assets	$ 44,869		$ 45,255
Lease liabilities	6,560		6,342
Lease liabilities, net of current portion	109,296		$ 111,027
Lease Cost
Total	4,289	$ 4,249
Research and development
Lease Cost
Operating lease cost	2,811	2,994
Variable lease cost	985	779
General and administrative expense
Lease Cost
Operating lease cost	493	476
Variable lease cost	$ 0	$ 0

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Amount of lease cost recognized by lessee for lease contract.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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