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Amount of interest expense on finance lease liability.

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

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Amount of lease cost recognized by lessee for lease contract.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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

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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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Leases - Components of lease expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020	Oct. 01, 2019
New Accounting Pronouncements and Changes in Accounting
(Accumulated deficits) Retained earnings	$ (254,639)		$ 174,248
Operating lease cost
Operating lease cost	47,500	$ 46,600
Finance lease cost
Amortization of right-of-use assets	2,500	4,700
Interest on lease liabilities	800	500
Variable lease cost	9,200	9,600
Short-term lease cost	2,000	3,400
Total lease cost	$ 62,000	$ 64,800
ASU 2016-02
New Accounting Pronouncements and Changes in Accounting
(Accumulated deficits) Retained earnings				$ (87,800)