Leases - Components of Lease Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Lease Assets and Liabilities
Right-of-use assets	$ 44,339		$ 44,339		$ 45,297
Lease liabilities	6,053		6,053		10,563
Lease liabilities, net of current portion	112,040		112,040		$ 104,608
Lease Cost
Total	4,365	$ 4,089	12,513	$ 9,904
Research and development
Lease Cost
Operating lease cost	2,965	3,323	8,531	7,735
Variable lease cost	863	257	2,478	627
General and administrative expense
Lease Cost
Operating lease cost	537	509	1,504	1,542
Variable lease cost	$ 0	$ 0	$ 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.

+ References

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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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- Definition

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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