Intangibles and Goodwill - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 17,357	$ 18,407	$ 13,095
Amortization expense, 2019	17,639
Amortization expense, 2020	15,893
Amortization expense, 2021	15,892
Amortization expense, 2022	15,550
Amortization expense, 2023	$ 15,177
Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	3 years
Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	20 years
Weighted average
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	14 years
Technology | Jet Prep Ltd.
Finite-Lived Intangible Assets [Line Items]
Accelerated amortization	$ 2,401