Other Income (Expense), Net (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Schedule of other (expense) income, net
Foreign currency transaction losses	$ (3)	$ (653)	$ (838)	$ (1,211)
Loss on sale of debt securities		(7)		(16)
Gain (loss) on investments	623	(66)	704	(7)
Other	(260)	14	(360)	66
Total other income (expense), net	$ 360	$ (712)	$ (494)	$ (1,168)

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Amount of realized and unrealized gain (loss) on investment.

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Amount of unrealized and realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of income (expense) related to nonoperating activities, classified as other.

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