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Weighted average basic and diluted number of common shares outstanding (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]
Basic weighted average number of shares	43,019,794	40,137,013	42,424,147	39,862,124
Effect of dilutive stock options and warrants
Diluted weighted average number of shares	43,019,794	40,137,013	42,424,147	39,862,124
Stock option [Member]
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]
Anti-dilutive stock	3,119,993	2,316,264	3,119,993	2,316,264
Warrant [Member]
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]
Anti-dilutive stock	4,091,623	5,859,843	4,091,623	5,859,843

X

- Definition

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2018-01-01
-Paragraph 70
-Subparagraph b
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-URIDate 2018-03-16

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- Definition

The number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 33
-IssueDate 2018-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2018-03-01&anchor=para_70_b&doctype=Standard
-URIDate 2018-03-16

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- Definition

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

+ References

No definition available.

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- Definition

The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2018-01-01
-Paragraph 70
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2018-03-01&anchor=para_70_b&doctype=Standard
-URIDate 2018-03-16

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Antidilutive stock.

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