| Income Taxes (Deferred Tax Asset Valuation Allowance Rollforward) (Details) - USD ($) | 12 Months Ended | |
|---|---|---|
| Apr. 30, 2017 | Apr. 30, 2016 | |
| Income Tax Disclosure [Abstract] | ||
| Valuation allowance, beginning of year | $ (9,068,774) | $ (8,240,200) | 
| (Increase) during period | (402,888) | (828,574) | 
| Valuation allowance, ending balance | $ (9,471,662) | $ (9,068,774) | 
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- References No definition available. 
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| X | ||||||||||
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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