Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (33,646)	$ (35,460)	$ (27,438)
Other comprehensive loss, net of tax:
Unrealized net losses on available-for-sale securities	(124)	0	0
Other comprehensive loss	(124)	0	0
Comprehensive loss	$ (33,770)	$ (35,460)	$ (27,438)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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