v3.3.1.900

Common shares (Details) $ / shares in Units, $ in Millions	3 Months Ended													12 Months Ended
	Mar. 03, 2016 USD ($) shares	Dec. 31, 2015 $ / shares	Dec. 31, 2015 CAD / shares	Sep. 30, 2015 $ / shares	Sep. 30, 2015 CAD / shares	Jun. 30, 2015 $ / shares	Jun. 30, 2015 CAD / shares	Mar. 31, 2015 $ / shares	Mar. 31, 2015 CAD / shares	Dec. 31, 2014 $ / shares	Sep. 30, 2014 $ / shares	Jun. 30, 2014 $ / shares	Mar. 31, 2014 $ / shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 $ / shares	Dec. 31, 2013 $ / shares
Stock Repurchase Program
Total Number of Shares Purchased | shares	575,553													47,300
Common stock repurchased, value | $	$ 1.0													$ 0.1
Common Share Dividends
Dividends paid per share | (per share)		$ 0.02	CAD 0.03	$ 0.02	CAD 0.03	$ 0.02	CAD 0.03	$ 0.03	CAD 0.03	$ 0.03	$ 0.07	$ 0.10	$ 0.10	$ 0.09	$ 0.29	$ 0.54

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- Definition

Stock Repurchase Program [Abstract]

+ References

No definition available.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: 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=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: 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=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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