Loss per share calculation (Details) - shares	3 Months Ended
Apr. 30, 2018	Apr. 30, 2017
Disclosure Of Earnings Per Share [Abstract]
Weighted average number of ordinary shares oustanding	76,571,101	61,883,701

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2017-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2017-03-01&anchor=para_70_b&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_WeightedAverageShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration