Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease expense	$ 6,132	$ 7,521
Finance lease expense:
Amortization of leased assets	32	0
Interest on lease liabilities	2	0
Variable lease expense	907	999
Sublease income	(123)	(351)
Total net lease expense	$ 6,950	$ 8,169

Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

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- References

No definition available.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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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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