Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Information on stock options outstanding (Details) - USD ($)	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Options Outstanding		18,095	18,095	19,639
Weighted Average Exercise Price per Share		$ 31.02	$ 31.02	$ 30.00
Options Aggregate Intrinsic Value	$ 10,719
Exercise Price 1
Options Range of Exercise Price	$ 1.00
Options Range of Exercise Price	$ 1.00
Options Outstanding	10,208
Weighted Average Exercise Price per Share	$ 1.00
Options Weighted Average Remaining Life (Years)	3 months
Options Aggregate Intrinsic Value	$ 11,058
Exercise Price 640
Options Range of Exercise Price	$ 640.00
Options Range of Exercise Price	$ 640.00
Options Outstanding	850
Weighted Average Exercise Price per Share	$ 640.00
Options Weighted Average Remaining Life (Years)	1 year 7 months