Leases - Components of Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Lease Cost
Operating lease cost	$ 32,912	$ 33,288	$ 32,402
Short-term lease cost	1,453	3,691	5,411
Variable lease cost	10,572	9,919	10,945
Sublease income	(958)	(1,436)	(4,749)
Total lease cost	$ 43,979	$ 45,462	$ 44,009

Amount of lease cost recognized by lessee for lease contract.

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- References

No definition available.

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- Definition

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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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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- Definition

Amount of sublease income excluding finance and operating lease expense.

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- Definition

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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