Leases - Related Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash outflow for operating leases	$ 23,260	$ 18,801
Operating cash outflow for finance leases	11	186
Finance Lease, Principal Payments	176	1,716	$ 945
Lease assets obtained in exchange for new lease liabilities:
Operating lease	5,413	11,457
Finance lease	$ 0	$ 1,387

Cash paid for amounts included in the measurement of lease liabilities: [Abstract]

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Lease assets obtained in exchange for new lease liabilities: [Abstract]

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- Definition

Amount of interest paid on finance lease liability.

+ References

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Amount of cash outflow for principal payment on finance lease.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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-Publisher FASB
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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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