Leases Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2021	Apr. 30, 2020	Apr. 30, 2021	Apr. 30, 2020	Jul. 31, 2020
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 7,040	$ 8,755	$ 21,321	$ 24,437
Amortization of right-of-use assets	167	341	501	653
Interest on finance lease liabilities	16	37	60	51
Short-term lease expense	1,037	3,784	3,305	7,076
Variable lease expense	278	382	1,212	1,201
Total lease expense	8,538	$ 13,299	26,399	$ 33,418
Operating lease right-of-use assets	$ 125,709		$ 125,709		$ 118,455

Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of amortization expense attributable to right-of-use asset from finance lease.

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- Definition

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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Amount of lessee's right to use underlying asset under operating lease.

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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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