Stockholders' Equity (Schedule of Warrants) (Details) - Warrant [Member] - USD ($) |
9 Months Ended | 12 Months Ended |
|---|---|---|
Jan. 31, 2018 |
Apr. 30, 2017 |
|
| Number of Shares | ||
| Balance Outstanding, April 30, 2017 | 914,123 | |
| Granted | 224,174 | |
| Exercised | (356,267) | |
| Forfeited | ||
| Expired | (38,257) | |
| Balance Outstanding, January 31, 2018 | 743,773 | 914,123 |
| Exercisable, October 31, 2017 | 743,773 | |
| Weighted Average Exercise Price | ||
| Balance Outstanding, April 30, 2017 | $ 2.82 | |
| Granted | 6.87 | |
| Exercised | 0.55 | |
| Forfeited | ||
| Expired | ||
| Balance Outstanding, January 31, 2018 | 4.08 | $ 2.82 |
| Exercisable, January 31, 2018 | $ 4.08 | |
| Weighted Average Remaining Contractual Term | ||
| Granted | 5 years | |
| Balance Outstanding, January 31, 2018 | 2 years 1 month 6 days | 1 year 7 months 6 days |
| Exercisable, January 31, 2018 | 2 years 1 month 6 days | |
| Aggregate Intrinsic Value | ||
| Balance Outstanding, April 30, 2017 | $ 1,100,203 | |
| Granted | 307,118 | |
| Balance Outstanding, January 31, 2018 | 3,095,502 | $ 1,100,203 |
| Exercisable, January 31, 2018 | $ 3,095,502 |
| 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.
|
| X | ||||||||||
- Definition Weighted average remaining contractual term for equity-based awards excluding options granted during the period, in ''PnYnMnDTnHnMnS'' format, for example, ''P1Y5M13D'' represents the reported fact of one year, five months, and thirteen days. No definition available.
|
| X | ||||||||||
- 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.
|
| X | ||||||||||
- Definition Intrinsic value of equity-based compensation awards granted during the period. Excludes stock and unit options. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- 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://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of non-option equity instruments exercised by participants. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of shares under non-option equity instrument agreements for which rights to exercise lapsed. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- 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://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Net number of non-option equity instruments granted to participants. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of equity instruments other than options outstanding, including both vested and non-vested instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| X | ||||||||||
- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
|
| X | ||||||||||
- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired. No definition available.
|
| X | ||||||||||
- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
|
| X | ||||||||||
- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options. No definition available.
|
| X | ||||||||||
- Definition Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options. No definition available.
|
| X | ||||||||||
- Details
|