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Income taxes - Expiration of non-capital losses for income tax purposes (Details) CAD in Thousands | Dec. 31, 2017 CAD
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Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | CAD 65,126
2025 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 2
2026 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 151
2027 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 128
2028 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 0
2029 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 0
2030 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 0
2031 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 604
2032 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 9,354
2033 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 13,829
2034 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 8,317
2035 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 0
2036 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | 5,691
2037 |
Operating Loss Carryforwards [Line Items] |
Operating loss carryforwards | CAD 27,050

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
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