Stockholders' Equity (Schedule of Warrants) (Details) - Warrant [Member] - USD ($) |
3 Months Ended | 12 Months Ended |
|---|---|---|
Jul. 31, 2019 |
Apr. 30, 2019 |
|
| Number of Shares | Ìý | Ìý |
| Balance Outstanding, April 30, 2019 | 731,152 | Ìý |
| Granted | Ìý | |
| Exercised | (43,860) | Ìý |
| Surrendered | Ìý | |
| Expired | Ìý | |
| Balance Outstanding, July 31, 2019 | 687,292 | 731,152 |
| Exercisable, July 31, 2019 | 637,292 | Ìý |
| Weighted Average Exercise Price | Ìý | Ìý |
| Balance Outstanding, April 30, 2019 | $ 5.28 | Ìý |
| Granted | Ìý | |
| Exercised | Ìý | |
| Surrendered | Ìý | |
| Expired | Ìý | |
| Balance Outstanding, July 31, 2019 | 5.47 | $ 5.28 |
| Exercisable, July 31, 2019 | $ 5.52 | Ìý |
| Weighted Average Remaining Contractual Term | Ìý | Ìý |
| Balance Outstanding, April 30, 2019 | 3 years 2 months 27 days | 3 years 3 months 15 days |
| Exercisable, July 31, 2019 | 3 years 1 month 16 days | Ìý |
| Aggregate Intrinsic Value | Ìý | Ìý |
| Balance Outstanding, April 30, 2019 | $ 413,296 | Ìý |
| Balance Outstanding, July 31, 2019 | 244,286 | $ 413,296 |
| Exercisable, July 31, 2019 | $ 244,286 | Ìý |
| X | ||||||||||
- Definition Weighted average remaining contractual term for equity-based awards excluding options that are currently exercisable, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available.
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- Definition Number of equity instruments other than options outstanding, into which fully or partially vested instruments outstanding as of the balance sheet date can be currently converted under the plan. No definition available.
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- References No definition available.
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- Definition Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of non-option equity instruments exercised by participants. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares under non-option equity instrument agreements for which rights to exercise lapsed. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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