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Stock-based compensation - Stock-based compensation expenses (Details) - General and administrative expenses - CAD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |
Stock-based compensation expenses | $ 11,532 | $ 3,995
Share option plan |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |
Stock-based compensation expenses | 97 | 326
Equity classified restricted share unit plan |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |
Stock-based compensation expenses | 2,110 | 1,293
Performance restricted share unit plan |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |
Stock-based compensation expenses | 1,910 | 1,306
Liability classified deferred stock unit plan |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |
Stock-based compensation expenses | $ 7,415 | $ 1,070

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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