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Other information Other information - Supplemental cash flow information (Details) - CAD CAD in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Cash paid during the year for: |  |
Interest | CAD 5,615 | CAD 5,895
Cash received during the year for: |  |
Interest | CAD 162 | CAD 194

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- Definition Cash Paid During the Year [Abstract] + References No definition available. + Details
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- Definition Cash Received During the Year [Abstract] + References No definition available. + Details
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- Definition Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585 + Details
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- Definition Interest received on loans and other debt instruments during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585 + Details
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