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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Date the equity-based award expires, in CCYY-MM-DD format.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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Percentage of vesting of share-based compensation awards.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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Number of shares related to Restricted Stock Award forfeited during the period.

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Share-Based Compensation (Details Narrative) - USD ($)		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
Share-Based Compensation (Details Narrative) - USD ($)	Dec. 13, 2016	Feb. 29, 2016	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016	Jul. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock					1,735,000		1,850,000
Option awards vesting percentage			25.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation			$ 251,000	$ 50,000	$ 712,000	$ 126,000
July 31, 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option awards vesting percentage			25.00%
October 31, 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option awards vesting percentage			25.00%
January 31, 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option awards vesting percentage			25.00%
2007 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares increase under the plan		4,000,000
Contractual life vesting periods		10 years
Number of shares available for issuance under the plan			561,000		561,000
Henry R. Lambert [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock						200,000
Officers and Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock					950,000
Officers and Directors [Member] \| RSU Cancellation Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of vested shraes of common stock	3,900,000
Pre-vest expense reversed	$ 87,000
Mark S. Elliott [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock						150,000
Pfanzelter [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock						200,000
Messrs. Cohee, Lee, Otis and Dr. Theno [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock						100,000
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock			600,000	740,000		110,000
Option awards vesting percentage				100.00%		100.00%
Third Party Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock			85,000
Scientific Advisory Board Member [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued to purchase common stock					100,000
Restricted Stock Units RSU [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding			1,110,000		1,110,000
Shares expected to vest					150,000
Unrecognized non-cash compensation costs			$ 24,000		$ 24,000
Unrecognized non-cash compensation costs, weighted average period					2 months 30 days
Share-based compensation			$ 23,000	$ 136,000	$ 98,000	$ 1,495,000
Restricted Stock Units RSU [Member] \| Key Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period, shares, share-based compensation						612,500
Restricted Stock Units RSU [Member] \| Henry R. Lambert [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period, shares, share-based compensation						200,000
Share-based compensation, expiration date						Jul. 31, 2018
Stock Option Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options were exercisable			2,258,593		2,258,593
Exercise price			$ 1.53		$ 1.53
Aggregate intrinsic value			$ 87,000		$ 87,000
Weighted-average contractual term of options outstanding					3 years 2 months 30 days
Weighted average grant date fair value for options granted					$ 0.43
Unrecognized compensation cost of unvested stock option grants			$ 497,000		$ 497,000
Weighted average period over grants are expected to vest					8 months 19 days