Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Stock-Based Compensation (Details Narrative)

v3.7.0.1

Stock-Based Compensation (Details Narrative) - USD ($)		12 Months Ended
Stock-Based Compensation (Details Narrative) - USD ($)	Jan. 19, 2016	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2015
Stock-based compensation expense		$ 476,000	$ 624,000
Number of shares granted			19,889
Warrant outstanding		33,415	51,905	275,689
Option Exchange Agreements [Member]
Stock-based compensation expense	$ 122,000
Employees, Officers and Board of Directors [Member]
Number of shares granted			19,889
Non-Employees [Member]
Number of common stock shares issued			28,000
Stock Appreciation Rights (SARs) [Member]
Share-based compensation arrangement by share-based payment award, exercised period		10 years
Restricted Stock Grants [Member]
Number of shares granted		55,083
Restricted Stock Grants [Member] \| Option Exchange Agreements [Member]
Options to purchase of shares	27,256
Incentive Stock Option [Member]
Option granted percentage		10.00%
Incentive Stock Option [Member] \| Maximum [Member]
Option granted percentage		110.00%
Stock Option [Member]
Forefiture rate		5.00%
Warrants [Member]
Warrant outstanding		33,417	51,906
Warrants [Member] \| Maximum [Member]
Warrants, exercise price		$ 42.00	$ 162.72
Warrants [Member] \| Minimum [Member]
Warrants, exercise price		$ 30.00	$ 30.00
2011 Incentive Option Plans [Member]
Number of shares allowed for granting under the plan		11,111
2014 Equity Incentive Plan [Member]
Number of common stock shares issued		20,833
Shares available for future grant		2,722
Share-based compensation arrangement by share-based payment award, exercised period		10 years
2011 Equity Incentive Plan and 2014 Equity Incentive Plan [Member] \| Option Exchange Agreements [Member]
Number of common stock shares issued	21,922

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Exercise price per share or per unit of warrants or rights outstanding.

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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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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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