Preferred shares (Details 2) (CAD)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Expected dividends paid per common share
Expected volatility in the price of common shares		65.00%	80.00%
Risk free interest rate		1.00%	1.20%
Preferred Shares [Member]
Expected dividends paid per common share	0
Expected life in years	1 year 10 months 24 days
Expected volatility in the price of common shares	62.00%
Risk free interest rate	1.00%
Weighted average fair value per Right at grant date	0.60

Amount of dividends expected to be paid to holders of the underlying shares or contracted instruments over the term of the instruments life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

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- Definition

Weighted average expected dividend for an entity using a valuation technique with different dividend rates during the contractual term.

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