Commitment and Contingencies - Net Lease Costs (Details) $ in Thousands	12 Months Ended
Sep. 30, 2020 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 6,557
Variable lease cost	1,353
Sublease income	(338)
Net lease cost	$ 7,572

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-SubTopic 20
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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