Income Taxes - Operating Loss Carryforwards (Details) - Foreign $ in Thousands	Jul. 31, 2018 USD ($)
Operating loss carryforwards
Net operating loss carryforwards (NOLs)	$ 8,605
Valuation allowance on NOLs	6,358
Jet Prep Ltd.
Operating loss carryforwards
Valuation allowance on NOLs	$ 2,785

The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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