Long term debt - Deferred Financing (Details) - CAD CAD in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Cost	CAD 2,377	CAD 235
Accumulated amortization	442	98
Net Book Value	1,935	137
Amortization of deferred financing costs	797	572
Convertible subordinated debentures
Debt Instrument [Line Items]
Amortization of deferred financing costs	CAD 344	CAD 410

Amount of accumulated amortization of debt issuance costs.

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Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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-Topic 225
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-Section S99
-Paragraph 2
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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+ References

No definition available.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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