Weighted average price of options that were exchanged under contractual agreement.

No definition available.

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- Definition

The number of shares under options that were exchanged during the reporting period as a result of occurrence of an event specified in contractual agreements pertaining to the stock option plan.

+ References

No definition available.

+ Details

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- Definition

The number of share warrants outstanding in connection with the financing arrangement.

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Future Incremental Compensation Cost

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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Share-Based Payments - Narrative (Details) - USD ($)			3 Months Ended				9 Months Ended
Share-Based Payments - Narrative (Details) - USD ($)	Jul. 21, 2016	Jul. 19, 2016	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense (in usd)			$ 237,000			$ 567,000	$ 1,901,000	$ 2,090,000
Weighted-average grant date fair value (in usd per share)			$ 1.35			$ 3.12	$ 1.71	$ 3.6
Shares granted		1,568,191					2,420,681
Shares exchanged during period		1,793,781
Grants in period, weighted average exercise price (in usd per share)		$ 2.10					$ 1.99
Warrants outstanding			2,109,840				2,109,840
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exchanges, weighted average exercise price (in usd per share)		4.55
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exchanges, weighted average exercise price (in usd per share)		$ 6.96
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Modification expense (in usd)	$ 414,756		$ 3,289	$ 38,590	$ 330,945
Modification expense for future period (in usd)	$ 41,932
November 5, 2013 [Member] \| Chief Executive Officer and President [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted							203,043
November 2016 [Member] \| Chief Executive Officer and President [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted							209,383