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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Commitments and Contingencies - Narrative (Details) - USD ($)	12 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017	Oct. 31, 2017
Total contractual obligations
Rent expense	$ 9,601,000	$ 8,801,000	$ 7,715,000
Litigation costs		$ 2,608,000
Aexis Medical
Total contractual obligations
Assumed contingent obligation	$ 1,411,000
Jet Prep Ltd.
Total contractual obligations
Assumed contingent obligation			$ 1,138,000	$ 0