Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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SEGMENT INFORMATION - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2020 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2020 USD ($) segment	Apr. 30, 2019 USD ($)	Jul. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment			2
Number of reportable segments \| segment			2
Total assets	$ 784,666		$ 784,666		$ 731,563
Revenues	177,351	$ 194,003	617,956	$ 615,359
United States
Segment Reporting Information [Line Items]
Revenues	117,315	133,790	417,028	416,228
China
Segment Reporting Information [Line Items]
Revenues	28,100	32,257	99,898	106,762
Netherlands
Segment Reporting Information [Line Items]
Revenues	9,467	11,534	31,185	40,881
Other
Segment Reporting Information [Line Items]
Revenues	$ 22,469	$ 16,422	$ 69,845	$ 51,488