Note 14 - Share Capital - Common Shares Outstanding (Details) - shares	12 Months Ended
Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Balance, beginning of year (in shares)	75,874,684	75,761,000	75,480,000
Stock options and share units exercised (in shares)	141,000	114,000	281,000
Acquisitions (Note 3) (in shares)	757,000
Balance, end of year (in shares)	76,773,497	75,874,684	75,761,000

Represents the number of shares issued from the exercise of stock options and share units.

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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