The amount of liability arising from an inherited contingency (as defined) which has been recognized as of the acquisition date.

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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 ($) $ in Thousands	3 Months Ended	12 Months Ended
	Apr. 30, 2018	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016	Oct. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Rent expense		$ 8,801	$ 7,715	$ 6,675
Total contractual obligations
Litigation costs	$ 2,608
Aexis Medical
Total contractual obligations
Assumed contingent obligation			1,298
Jet Prep Ltd.
Total contractual obligations
Assumed contingent obligation			$ 1,138		$ 0