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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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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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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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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Segment Information - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2018 USD ($)	Jan. 31, 2017 USD ($)	Jan. 31, 2018 USD ($) Segment	Jan. 31, 2017 USD ($)	Jul. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| Segment			5
Number of reportable segments \| Segment			4
Total assets	$ 870,110		$ 870,110		$ 281,298
Net revenue	151,119	$ 117,568	253,641	$ 238,895
United States
Segment Reporting Information [Line Items]
Total assets	567,600		567,600		$ 9,300
Net revenue	72,000	27,500	87,100	54,300
China
Segment Reporting Information [Line Items]
Net revenue	28,200	31,900	63,000	68,100
Netherlands
Segment Reporting Information [Line Items]
Net revenue	16,500	20,000	31,800	36,800
Czech Republic
Segment Reporting Information [Line Items]
Net revenue	$ 18,300	$ 21,700	$ 40,800	$ 48,000