Income Taxes (Details 4) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Reserves deducted from deferred income taxes, net:
Valuation allowance - Balance at beginning of year	$ 76,020	$ 129,872	$ 130,498
Valuation allowance - Additions charged to costs and expenses			16,017
Valuation allowance - Deductions	(1,850)	(53,852)	(16,643)
Valuation allowance - Balance at end of year	$ 74,170	$ 76,020	$ 129,872

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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-Publisher FASB
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- Definition

Amount of valuation allowance of deferred tax asset attributable to deductible temporary differences and carryforwards, classified as current.

+ References

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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Amount of decrease in valuation and qualifying accounts and reserves.

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